WO2024084336A1 - Metal powder for additive manufacturing - Google Patents
Metal powder for additive manufacturing Download PDFInfo
- Publication number
- WO2024084336A1 WO2024084336A1 PCT/IB2023/060222 IB2023060222W WO2024084336A1 WO 2024084336 A1 WO2024084336 A1 WO 2024084336A1 IB 2023060222 W IB2023060222 W IB 2023060222W WO 2024084336 A1 WO2024084336 A1 WO 2024084336A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- powder
- anyone
- metal powder
- layer
- laser
- Prior art date
Links
- 239000000843 powder Substances 0.000 title claims abstract description 74
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 37
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 32
- 239000002184 metal Substances 0.000 title claims abstract description 32
- 239000000654 additive Substances 0.000 title claims abstract description 23
- 230000000996 additive effect Effects 0.000 title claims abstract description 23
- 238000000034 method Methods 0.000 claims abstract description 36
- 239000000203 mixture Substances 0.000 claims abstract description 27
- 230000008569 process Effects 0.000 claims abstract description 25
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 19
- 239000012535 impurity Substances 0.000 claims abstract description 7
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 7
- 229910052758 niobium Inorganic materials 0.000 claims abstract description 7
- 229910052742 iron Inorganic materials 0.000 claims abstract description 6
- 229910052721 tungsten Inorganic materials 0.000 claims abstract description 6
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 6
- 229910052715 tantalum Inorganic materials 0.000 claims abstract description 5
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 5
- 229910052726 zirconium Inorganic materials 0.000 claims abstract description 5
- 230000001955 cumulated effect Effects 0.000 claims abstract description 4
- 239000002245 particle Substances 0.000 claims description 22
- 239000007789 gas Substances 0.000 claims description 17
- 229910052748 manganese Inorganic materials 0.000 claims description 16
- 238000002844 melting Methods 0.000 claims description 14
- 230000008018 melting Effects 0.000 claims description 14
- 238000007711 solidification Methods 0.000 claims description 13
- 230000008023 solidification Effects 0.000 claims description 13
- 150000001247 metal acetylides Chemical class 0.000 claims description 9
- 229910000859 α-Fe Inorganic materials 0.000 claims description 8
- 239000012159 carrier gas Substances 0.000 claims description 5
- 230000001413 cellular effect Effects 0.000 claims description 5
- 230000004927 fusion Effects 0.000 claims description 5
- 238000001465 metallisation Methods 0.000 claims description 5
- 239000011261 inert gas Substances 0.000 claims description 4
- 229910001092 metal group alloy Inorganic materials 0.000 claims description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 24
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 18
- 239000011572 manganese Substances 0.000 description 17
- 229910052782 aluminium Inorganic materials 0.000 description 14
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 13
- 229910052757 nitrogen Inorganic materials 0.000 description 13
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 12
- 229910052799 carbon Inorganic materials 0.000 description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 10
- 229910000831 Steel Inorganic materials 0.000 description 9
- 229910052759 nickel Inorganic materials 0.000 description 9
- 239000010959 steel Substances 0.000 description 9
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 8
- 229910045601 alloy Inorganic materials 0.000 description 8
- 239000000956 alloy Substances 0.000 description 8
- 229910052786 argon Inorganic materials 0.000 description 8
- 230000015572 biosynthetic process Effects 0.000 description 8
- 210000004027 cell Anatomy 0.000 description 8
- 239000011651 chromium Substances 0.000 description 8
- 229910001566 austenite Inorganic materials 0.000 description 7
- 230000007423 decrease Effects 0.000 description 7
- 229910001021 Ferroalloy Inorganic materials 0.000 description 6
- 229910052804 chromium Inorganic materials 0.000 description 6
- 238000001816 cooling Methods 0.000 description 6
- 238000001556 precipitation Methods 0.000 description 6
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 5
- 238000005275 alloying Methods 0.000 description 5
- 229910052796 boron Inorganic materials 0.000 description 5
- 229910052734 helium Inorganic materials 0.000 description 5
- 239000010955 niobium Substances 0.000 description 5
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 4
- 238000000889 atomisation Methods 0.000 description 4
- 238000005336 cracking Methods 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 239000000155 melt Substances 0.000 description 4
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 239000001307 helium Substances 0.000 description 3
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 239000011733 molybdenum Substances 0.000 description 3
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 229910052710 silicon Inorganic materials 0.000 description 3
- 238000005728 strengthening Methods 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- 239000010936 titanium Substances 0.000 description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 2
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 210000004443 dendritic cell Anatomy 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000009689 gas atomisation Methods 0.000 description 2
- 238000004372 laser cladding Methods 0.000 description 2
- -1 manganese aluminum Chemical compound 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 238000013021 overheating Methods 0.000 description 2
- 229910052698 phosphorus Inorganic materials 0.000 description 2
- 238000007639 printing Methods 0.000 description 2
- 238000001878 scanning electron micrograph Methods 0.000 description 2
- 238000000110 selective laser sintering Methods 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 229910052717 sulfur Inorganic materials 0.000 description 2
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- GPPXJZIENCGNKB-UHFFFAOYSA-N vanadium Chemical compound [V]#[V] GPPXJZIENCGNKB-UHFFFAOYSA-N 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 229910000640 Fe alloy Inorganic materials 0.000 description 1
- 229910015372 FeAl Inorganic materials 0.000 description 1
- 229910015136 FeMn Inorganic materials 0.000 description 1
- 229910002555 FeNi Inorganic materials 0.000 description 1
- 229910005347 FeSi Inorganic materials 0.000 description 1
- 229910000604 Ferrochrome Inorganic materials 0.000 description 1
- 229910001111 Fine metal Inorganic materials 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 229910052769 Ytterbium Inorganic materials 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000000149 argon plasma sintering Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 229910001567 cementite Inorganic materials 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000004320 controlled atmosphere Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007123 defense Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- KSOKAHYVTMZFBJ-UHFFFAOYSA-N iron;methane Chemical compound C.[Fe].[Fe].[Fe] KSOKAHYVTMZFBJ-UHFFFAOYSA-N 0.000 description 1
- PYLLWONICXJARP-UHFFFAOYSA-N manganese silicon Chemical compound [Si].[Mn] PYLLWONICXJARP-UHFFFAOYSA-N 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000012798 spherical particle Substances 0.000 description 1
- 238000005482 strain hardening Methods 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 238000007669 thermal treatment Methods 0.000 description 1
- 238000011282 treatment Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- NAWDYIZEMPQZHO-UHFFFAOYSA-N ytterbium Chemical compound [Yb] NAWDYIZEMPQZHO-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/05—Metallic powder characterised by the size or surface area of the particles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
- B22F10/20—Direct sintering or melting
- B22F10/25—Direct deposition of metal particles, e.g. direct metal deposition [DMD] or laser engineered net shaping [LENS]
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
- B22F10/20—Direct sintering or melting
- B22F10/28—Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
- B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
- B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y10/00—Processes of additive manufacturing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y70/00—Materials specially adapted for additive manufacturing
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/02—Making ferrous alloys by powder metallurgy
- C22C33/0257—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
- C22C33/0278—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements with at least one alloying element having a minimum content above 5%
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/25—Process efficiency
Definitions
- the present invention relates to a metal powder for the manufacturing of steel parts and in particular for their additive manufacturing.
- the present invention also relates to the method for manufacturing the metal powder.
- the powder according to the invention is particularly well suited for the manufacture of safety or structural parts with a low density, for vehicles such as land motor vehicles. It can also be used, notably for manufacturing parts for defense, navy, or armoring applications.
- Their solidified structure shows an austenitic structure possibly comprising kappa carbide (Fe,Mn)3AICx and ferrite.
- the aim of the present invention is therefore to remedy the drawbacks of the prior art by providing a new way to obtain parts with low density without manufacturability issues.
- a first object of the present invention consists of a metal powder for additive manufacturing having a composition comprising the following elements, expressed in content by weight:
- N ⁇ 0.100% and optionally containing Ni ⁇ 8.5 wt.% and/or Cr ⁇ 2.5 wt.% and/or B ⁇ 0.1 wt.% and/or one or more elements chosen among Ta, Zr, Nb, V, Ti, Mo, and W in a cumulated amount of up to 2.0 wt.%, the balance being iron and unavoidable impurities resulting from the elaboration.
- the metal powder according to the invention may also have the optional features listed below, considered individually or in combination:
- the powder particles have an austenitic microstructure comprising up to 1 weight % of kappa carbides (Fe,Mn)sAICx and up to 20 weight % of ferrite and up to 1 weight % of AIN,
- the powder has a density below 7.0 g/cm 3 ,
- the average particle size ranks from 60 to 150 pm.
- a second object of the invention consists of a process for manufacturing a metal powder for additive manufacturing, comprising:
- a third object of the invention consists of a process for manufacturing a printed part by additive manufacturing wherein a powder according the invention is printed by Laser Powder Bed Fusion.
- the printing process according to the invention may also have the optional features listed below, considered individually or in combination: - the process comprises a first step of forming a powder layer with a thickness below 100 pm and a second step where a focused laser beam forms a shaped layer by melting at least part of the powder layer in an atmosphere substantially composed of an inert gas, the process is set with the following parameters: the laser power is limited to maximum 500 W, the scan speed is from 300 to 2000 mm/s, the Linear Energy Density is from 190 to 500 J/m, the hatch spacing is from 50 to 120 pm, The Volumetric Energy Density is from 100 to 330 J/mm3.
- a fourth object of the invention consists of a printed part obtained according to the invention having a cellular solidification structure with an equivalent diameter below 2 pm.
- Manganese is present in the composition according to the invention at a content of 15 to 35 wt.%.
- Manganese is an essential alloying element for such grade, mainly due to the fact that alloying with very high amounts of manganese and carbon stabilizes, in the final part, the austenite down to room temperature, which can then tolerate high amounts of aluminum without being destabilized and transformed into too much ferrite or into martensite.
- the manganese content has to be equal or higher to 15 wt.%.
- the precipitation of [3-Mn phase will deteriorate the ductility of the alloy.
- the manganese content should be controlled to be equal or greater than 15 wt.%, but lower than equal to 35 wt.%. In a preferred embodiment, it is equal or greater than 15.5 wt.% or even than 16.0 wt.%. Its amount is more preferably from 25 to 31 wt.%, or even better from 26 to 30 wt.%.
- Aluminum is present in the composition according to the invention at a content of 6 to 15 wt.%. Aluminum addition to high manganese austenitic steels effectively decreases the density of the alloy. In addition, it considerably increases the stacking fault energy (SFE) of the austenite in the final part, leading in turn to a change in the strain hardening behavior of the alloy.
- SFE stacking fault energy
- Aluminum is also one of the primary elements of nanosized kappa carbide (Fe,Mn)3AICx and therefore its addition significantly enhances the formation of such carbides.
- the aluminum concentration of the present alloys should be adjusted, on one hand, to guarantee the austenite stability and the possible precipitation of kappa carbides, and on the other to control the formation of ferrite.
- an aluminum amount below 6 wt.% leads to a density of the material higher than 7.0 g/cm 3 in the final part. Therefore, the aluminum content should be controlled to be equal or greater than 6 wt.%, but lower than or equal to 15 wt.% to avoid removing the austenitic phase.
- aluminum content is from 6 to 12 wt.%, or even better from 6 to 10 wt.%.
- the carbon content is set at 0.5 to 1 .8 wt.%.
- Carbon plays an important role in the formation of the microstructure of the final part. Its main role is to stabilize austenite which is the main phase of the microstructure of the steel part as well as to provide strengthening. Carbon content below 0.5 wt.% will decrease the proportion of austenite, which leads to the decrease of both ductility and strength of the alloy.
- a carbon content above 1.8 wt.% can promote the precipitation of such carbides in a coarse manner on the grain boundaries, which results in the decrease of the ductility of the alloy.
- the carbon content is from 0.6 to 1 .3 wt.%, more preferably from 0.8 to 1 .2% by weight so as to obtain sufficient strength.
- Silicon is present in the composition according to the invention at a content from 0 to 0.5 wt.%. It has been observed that the addition of up to 0.5 wt.% of silicon was suppressing hot cracking that occurs when producing the final part by additive manufacturing. However, an addition above 0.5 wt.% leads to cold cracking failure when producing the final part by additive manufacturing. Preferred ranges are from 0.05 to 0.5 wt.%, from 0 to 0.25 wt.% or even better from 0.05 to 0.25 wt.%. Nickel may be optionally present in a content up to 8.5 wt.%. Nickel can be used as a diffusion barrier to hydrogen.
- Nickel amount higher than 8.5 wt.% is not desired because it promotes the formation of cementite in detriment of the (Fe,Mn)3AICx carbides.
- Nickel can also be used as an effective alloying element because it stabilizes the austenite, and also promotes the formation of ordered compounds in ferrite, such as the B2 component, leading to additional strengthening.
- the composition may however comprise up to 0.1 wt.% of nickel as an impurity.
- Chromium may be optionally present in a content up to 2.5 wt.% for increasing the strength of the steel by solution hardening. It also enhances the high temperature corrosion resistance of the steels according to the invention. However, since chromium reduces the stacking fault energy and the stability of austenite, its content must not exceed 2.5 wt.% and preferably from 0.1 % to 2.0 wt.% or from 0.1 to 1 .0 wt.%. When chromium is not added, the composition may however comprise up to 0.1 wt.% of Cr as an impurity.
- Boron may be optionally present in a content up to 0.1 wt%. Boron has a very low solid solubility and a strong tendency to segregate at the grain boundaries, interacting strongly with lattice imperfections. Therefore, boron can be used to limit the precipitation of intergranular kappa carbides.
- Tantalum, zirconium, niobium, vanadium, titanium, molybdenum and tungsten are elements that may optionally be used to achieve hardening and strengthening, notably by precipitation of nitrides, carbo-nitrides or carbides.
- their cumulated amount is above 2.0 wt.%, preferably above 1.0 wt.%, or even better above 0.5 or above 0.3 wt.%, there is a risk that an excessive precipitation may cause a reduction in toughness, which has to be avoided.
- the balance is made of iron and unavoidable impurities resulting from the elaboration.
- Phosphorus, sulfur and nitrogen are the main impurities. They are not deliberately added. They might notably be present in the ferroalloys and/or pure elements used as raw materials.
- Nitrogen can also be introduced during atomization.
- Their content is preferably controlled to avoid changing detrimentally the microstructure and/or to avoid increasing the brittleness. Therefore, their content is respectively limited to 0.013wt.%, to 0.015 wt.% and to 0.1 wt.%. In a preferred embodiment, their content is respectively limited to 0.005 wt.% to 0.015 wt.% and to 0.01 wt.%.
- the microstructure of the powder is mainly austenitic and may optionally include up to 1 wt.% of kappa carbides (Fe,Mn)3AICx, up to 1 wt. % of AIN and up to 20 wt.% of ferrite.
- the optional ferrite content can be from 0.5 to 10 wt.% or from 0.5 to 5 wt.% or even better from 0.5 to 4.0 wt.%.
- the powder can be obtained by first mixing and melting pure elements and/or ferroalloys as raw materials. It can also be obtained by using a pre-alloyed ingot of the required composition.
- Ferroalloys refer to various alloys of iron with a high proportion of one or more other elements such as manganese silicon, aluminum, niobium, boron, chromium, molybdenum....
- the main alloys are FeMn (usually comprising 70 to 80 wt.% Mn), FeAl (usually comprising 40 to 60 wt.% Al), FeSi (usually comprising 15 to 90 wt.% Si), FeNi (usually comprising 70 to 95 wt.% Ni), FeB (usually comprising 17.5 to 20 wt.% B ), FeCr (usually comprising 50 to 70 wt.% Cr), FeMo (usually comprising 60 to 75 wt.% Mo), FeNb (usually comprising 60 to 70 wt.% Nb), FeV (usually comprising 35 to 85 wt.% V), FeW (usually comprising 70 to 80 wt.% W).
- FeMn usually comprising 70 to 80 wt.% Mn
- Alloying elements can be alternatively added as pure elements (usually with a purity over 99 wt.%).
- Pure elements can notably be carbon and pure metals such as iron, aluminum, manganese or nickel, zirconium, titanium, tantalum, molybdenum, tungsten, niobium, vanadium, chromium.
- the composition is heated at a temperature at least 100 °C above its liquidus temperature and maintain at this temperature to melt all the raw materials and homogenize the melt. Thanks to this overheating, the decrease in viscosity of the melted composition helps obtaining a powder with a high sphericity without satellites and with a proper particle size distribution. That said, as the surface tension increases with temperature, it is preferred not to heat the composition at a temperature more than 450 °C above its liquidus temperature.
- the composition is heated at a temperature at least 200 °C above its liquidus temperature so as to promote the formation of highly spherical particles. More preferably, the composition is heated at a temperature 250 °C above its liquidus temperature.
- the composition is heated from 1650 to 1800 °C which represents a good compromise between viscosity decrease and surface tension increase.
- the molten composition is then atomized into fine metal droplets by forcing a molten metal stream through an orifice, the nozzle, at moderate pressures and by impinging it with jets of gas (gas atomization).
- gas gas atomization
- the gas is introduced into the metal stream just before it leaves the nozzle, serving to create turbulence as the entrained gas expands (due to heating) and exits into a large collection volume, the atomizing tower.
- the latter is filled with gas to promote further turbulence of the molten metal jet.
- the metal droplets cool down during their fall in the atomizing tower. Gas atomization is preferred because it favors the production of powder particles having a high degree of roundness and a low number of satellites.
- the atomization gas is preferably argon or nitrogen or a mixture thereof. They both increase the melt viscosity slower than other gases, e.g., helium, which promotes the formation of smaller particle sizes. They also control the purity of the chemistry and play a role in the good morphology of the powder. Finer particles can usually be obtained with argon than with nitrogen since the molar weight of nitrogen is 14.01 g/mole compared with 39.95 g/mole for argon. On the other hand, the specific heat capacity of nitrogen is 1 .04 J/(g K) compared with 0.52 for argon. So, nitrogen increases the cooling rate of the particles. Whenever nitrogen is used as a component of the atomization process, up to 1 weight % of AIN can be formed through the combination of aluminium and nitrogen.
- the gas pressure is of importance since it directly impacts the particle size distribution.
- the higher the pressure the higher the cooling rate.
- the gas pressure is set from 10 to 30 bar, or even better from 24 to 30 bar, to promote the formation of particles whose size is most compatible with the additive manufacturing techniques.
- the nozzle diameter has an impact on the molten metal flow rate and, thus, on the particle size distribution and on the cooling rate.
- the nozzle diameter is preferably limited to 4 mm to limit the increase in mean particle size and the decrease in cooling rate.
- the metal powder obtained by atomization can be either used as such or can be sieved to keep the particles whose size better fits the additive manufacturing technique to be used afterwards.
- the range 20-63 pm (called fraction F2) is preferred and the range 20-40 pm is even better.
- the range 60-150 pm (called F3) is preferred and the range 40-125 pm is even better.
- Fraction F1 covering particles sizes below 20 pm or even 10 pm can be used for example in binder jetting.
- the parts made of the metal powder according to the invention can be obtained by additive manufacturing techniques such as Powder Bed Fusion (LPBF), Direct metal laser sintering (DMLS), Electron beam melting (EBM), Selective heat sintering (SHS), Selective laser sintering (SLS), Laser Metal Deposition (LMD), Direct Metal Deposition (DMD), Direct Metal Laser Melting (DMLM), Direct Metal Printing (DMP), Laser Cladding (LC), Binder Jetting (BJ), Cold Spray (CS), Thermal Spray (TS), High Velocity Oxygen Fuel (HVOF).
- LPBF Powder Bed Fusion
- DMLS Direct metal laser sintering
- EBM Electron beam melting
- SHS Selective heat sintering
- SLS Selective laser sintering
- LMD Laser Metal Deposition
- DMD Direct Metal Deposition
- DMLM Direct Metal Laser Melting
- DMP Direct Metal Printing
- LC Laser Cladding
- BJ Cold Spray
- CS Thermal Spray
- HVOF High Velocity Oxygen Fuel
- the invention can make use of LPBF process which is a layer- upon-layer additive manufacturing technique.
- Thin layers of metal powder are evenly distributed using a coating mechanism onto a substrate platform, usually metal, that is fastened to an indexing table that moves in the vertical axis. This takes place inside a chamber containing a tightly controlled atmosphere.
- a high-power laser beam usually an ytterbium fiber laser.
- the laser energy is intense enough to permit full melting (welding) of the particles in the form of a track or strip. Basically, once a track is done, the process is repeated with the next track, which is separated from the first one by the hatch spacing.
- the process is repeated layer after layer until the part is complete.
- the overhanging geometry is supported by nonmelted powder from previous layers.
- the main process parameters used in LPBF are usually the layer thickness, the hatch spacing, the scan speed and the laser power.
- the left-over powder is screened to be reused.
- the process for producing an additively manufactured part by LPBF comprises a first step of forming a powder layer with the powder according to the invention.
- the powder layer is less than 100 pm. Above 100 pm, the laser might not melt the powder in all the layer thickness, which might lead to porosity in the part.
- the layer thickness is kept from 20 to 60 pm to optimize the melting of the powder.
- a focused laser beam forms a shaped layer by melting at least part of the powder layer in the process conditions detailed below.
- each layer of the printed part is at least partially melted in an atmosphere substantially composed of an inert gas.
- the laser power is preferably limited to maximum 500 W.
- the laser power is set above 80W to ease the melting in all the layer thickness.
- the laser power is from 175 to 300 W.
- the scan speed is preferably from 300 to 2000 mm/s and more preferably from 300 to 700 mm/s.
- 300 mm/s the excess energy provided by the laser might lead key-hole porosity and/or to spatters which, if not properly drag outside of the powder bed, deposit on the powder layer which create voids in the printed part.
- 2000 mm/s the energy provided by the laser to the powder might not be enough to melt the powder in all the layer thickness.
- the Linear Energy Density is preferably from 190 to 500 J/m. LED is defined as the ratio between the laser power and the scan speed expressed in m/s. Below 190 J/m, LED might not be enough to properly print parts (due to keyholing). Above 400 J/m, the excess energy provided by the laser might lead to spatters which, if not properly drag outside of the powder bed, deposit on the powder layer. Such deposits create voids in the printed part.
- the hatch spacing is preferably from 50 to 120 pm. Below 50 pm, each point of the printed part might be remelted multiple times which might lead to overheating. Above 120 pm, non-melted powder might be trapped between two tracks. More preferably, the hatch spacing is from 70 to 110 pm.
- VED Volumetric Energy Density
- P the laser power
- v the scan speed
- h the hatch spacing
- It the powder layer thickness.
- the invention can alternatively make use of LMD process which is a layer- upon-layer additive manufacturing technique.
- LMD laser beam forms a melt pool on a metallic substrate, into which powder is fed through a carrier gas.
- the powder melts under the protection of a shielding gas to form a deposit that is fusion bonded to the substrate.
- the required geometry is built up in this way, layer by layer thanks to a gantry system or a robotic arm that control both the laser and the powderdelivery nozzle.
- the laser power is preferably from 600 to 1000W.
- the laser power is set from 600 to 800W.
- the scan speed is preferably from 5 to 40 mm/s and more preferably from 15 to 30 mm/s.
- the powder feed rate is preferably from 5 to 40 g/min and more preferably from 10 to 25 g/min.
- the layer thickness is preferably from 0.2 to 1.5 mm and more preferably from 0.4 to 1 mm.
- the laser spot diameter is preferably from 0.5 to 4 mm and more preferably from 1 to 3 mm.
- the laser beam shape can be gaussian or top hat.
- the carrier gas can be selected among nitrogen, helium or argon or their mixtures and its flow rate is preferably from 2 to 8 l/min and more preferably from 4 to 6 l/min.
- the shielding gas can be selected among nitrogen, helium or argon or their mixtures and its flow rate is preferably from 8 to 20 l/min. and more preferably from 10 to 15 l/min.
- the microstructure of the parts can be different but are in each case solidification microstructures.
- Such solidification microstructures are determined by the temperature gradient (G) and growth rate (R) as they involve high cooling rates typical of additive manufacturing methods [Kou, S. (2020). Welding metallurgy. John Wiley & Sons],
- P, S and N were respectively maintained below 0.013 wt.%, 0.015 wt.% and 0.1 wt.%.
- fraction F2 of such powders was then used to print series of 22 cubes of 1 cm 3 by LPBF, using the following parameters:
- VED Volumetric Energy Density
- microstructure of the printed cubes using powder 1 was assessed and shows solidification cellular cells with an equivalent diameter below 2 pm. Such cell sizes were determined by the line intercept method of ASTM E112-10 standard by using transverse SEM micrographs.
- the printed cubes corresponding to powder 1 were then submitted to different heating treatments and finally water quenched, to evaluate the evolution of their hardness, measured according to standard ASTM E92-17 for the heating temperatures and times as shown in Table 5.
- fraction F3 of such powder 1 was then used to print series of prisms of 1 .5 cm 3 with LMD technology, using the following parameters:
- Laser beam shape Gaussian or Top Hat
- Carrier gas N2, He or Ar
- Carrier gas flow from 4 to 6 L/min
- microstructure of the printed cubes was determined by XRD and gathered in Table 8.
- the microstructure of the printed cubes using powder 1 was assessed and shows a combination of solidification cells: Cellular-dendritic cells with an equivalent diameter below 10 m and columnar dendritic cells with an equivalent diameter from 10 to 20 pm. Such cell sizes were determined by the line intercept method of ASTM E112-10 standard by using transverse SEM micrographs.
- the printed cubes corresponding to powder 1 were then submitted to different isothermal heat treatments and finally water-quenched, to evaluate the evolution of their hardness, measured according to standard ASTM E92-17 for the temperatures and times as shown in Table 9.
- the evolution of their mechanical properties, as evaluated using the ASTM standard E8/E8M-16a subsize is also gathered in table 9:
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Powder Metallurgy (AREA)
Abstract
The invention relates to a metal powder for additive manufacturing having a composition comprising the following elements, expressed in content by weight: − 15% ≤ Mn ≤ 35% − 6% ≤ Al ≤ 15% − 0.5% ≤ C ≤ 1.8% − 0% ≤ Si ≤ 0.5% − P ≤ 0.013% − S ≤ 0.015% − N ≤ 0.100% and optionally containing Ni ≤ 8.5 wt.% and/or Cr ≤ 2.5 wt.% and/or B ≤ 0.1 wt.% and/or one or more elements chosen among Ta, Zr, Nb, V, Ti, Mo, and W in a cumulated amount of up to 2.0 wt.%, the balance being iron and unavoidable impurities resulting from the elaboration. It also deals with a process for manufacturing such powder and for manufacturing a printed part out of it.
Description
Metal powder for additive manufacturing
The present invention relates to a metal powder for the manufacturing of steel parts and in particular for their additive manufacturing. The present invention also relates to the method for manufacturing the metal powder. The powder according to the invention is particularly well suited for the manufacture of safety or structural parts with a low density, for vehicles such as land motor vehicles. It can also be used, notably for manufacturing parts for defense, navy, or armoring applications.
Environmental restrictions are forcing automakers to continuously reduce the CO2 emissions of their vehicles. To do that, automakers are looking at every way to reduce the weight of the motor vehicles.
This can in particular be achieved by reducing the density of the steels used for manufacturing parts, by alloying them with other, lighter metals than iron.
Steels containing high levels of manganese aluminum and carbon often referred to as triplex steels, can show density levels below 7.4 g/cm3. Their solidified structure shows an austenitic structure possibly comprising kappa carbide (Fe,Mn)3AICx and ferrite.
However, they are difficult to manufacture by conventional casting methods due to their high aluminum and carbon amounts. They also exhibit some macrosegregations of manganese, carbon and/or aluminum, generating bands when they are laminated and possibly forming brittle phases leading to cracks.
The aim of the present invention is therefore to remedy the drawbacks of the prior art by providing a new way to obtain parts with low density without manufacturability issues.
For this purpose, a first object of the present invention consists of a metal powder for additive manufacturing having a composition comprising the following elements, expressed in content by weight:
- 15% < Mn < 35%
- 6% < Al < 15%
- 0.5% < C < 1.8%
- 0 < Si < 0.5%
- P < 0.013%
- S < 0.015%
- N < 0.100% and optionally containing Ni < 8.5 wt.% and/or Cr < 2.5 wt.% and/or B < 0.1 wt.% and/or one or more elements chosen among Ta, Zr, Nb, V, Ti, Mo, and W in a cumulated amount of up to 2.0 wt.%, the balance being iron and unavoidable impurities resulting from the elaboration.
The metal powder according to the invention may also have the optional features listed below, considered individually or in combination:
- the powder particles have an austenitic microstructure comprising up to 1 weight % of kappa carbides (Fe,Mn)sAICx and up to 20 weight % of ferrite and up to 1 weight % of AIN,
- the powder has a density below 7.0 g/cm3,
- the average particle size ranks from 1 to 150 pm,
- the average particle size ranks from 1 to 20 pm,
- the average particle size ranks from 20 to 63 pm,
- the average particle size ranks from 60 to 150 pm.
A second object of the invention consists of a process for manufacturing a metal powder for additive manufacturing, comprising:
- a) Melting elements and/or metal-alloys at a temperature at least 100°C above the liquidus temperature so as to obtain a molten composition according to claim 1 ,
- b) Atomizing the molten composition through a nozzle the diameter of which is at most 4mm, with a gas pressurized from 10 to 30 bar.
A third object of the invention consists of a process for manufacturing a printed part by additive manufacturing wherein a powder according the invention is printed by Laser Powder Bed Fusion.
The printing process according to the invention may also have the optional features listed below, considered individually or in combination:
- the process comprises a first step of forming a powder layer with a thickness below 100 pm and a second step where a focused laser beam forms a shaped layer by melting at least part of the powder layer in an atmosphere substantially composed of an inert gas, the process is set with the following parameters: the laser power is limited to maximum 500 W, the scan speed is from 300 to 2000 mm/s, the Linear Energy Density is from 190 to 500 J/m, the hatch spacing is from 50 to 120 pm, The Volumetric Energy Density is from 100 to 330 J/mm3.
A fourth object of the invention consists of a printed part obtained according to the invention having a cellular solidification structure with an equivalent diameter below 2 pm.
The invention will be better understood by reading the following description, which is provided purely for purposes of explanation and is in no way intended to be restrictive.
Manganese is present in the composition according to the invention at a content of 15 to 35 wt.%. Manganese is an essential alloying element for such grade, mainly due to the fact that alloying with very high amounts of manganese and carbon stabilizes, in the final part, the austenite down to room temperature, which can then tolerate high amounts of aluminum without being destabilized and transformed into too much ferrite or into martensite. To enable the alloy to have a superior ductility, the manganese content has to be equal or higher to 15 wt.%. However, when the manganese content is over 35 wt.%, the precipitation of [3-Mn phase will deteriorate the ductility of the alloy. Therefore, the manganese content should be controlled to be equal or greater than 15 wt.%, but lower than equal to 35 wt.%. In a preferred embodiment, it is equal or greater than 15.5 wt.% or even than 16.0 wt.%. Its amount is more preferably from 25 to 31 wt.%, or even better from 26 to 30 wt.%.
Aluminum is present in the composition according to the invention at a content of 6 to 15 wt.%. Aluminum addition to high manganese austenitic steels effectively decreases the density of the alloy. In addition, it considerably increases the stacking fault energy (SFE) of the austenite in the final part, leading in turn to a change in the strain hardening behavior of the alloy. Aluminum is also one of the primary elements of nanosized kappa carbide (Fe,Mn)3AICx and therefore its addition significantly enhances the formation of such carbides. The aluminum concentration of the present alloys should be adjusted, on one hand, to guarantee the austenite stability and the possible precipitation of kappa carbides, and on the other to control the formation of ferrite. Moreover, it has been observed that an aluminum amount below 6 wt.% leads to a density of the material higher than 7.0 g/cm3 in the final part. Therefore, the aluminum content should be controlled to be equal or greater than 6 wt.%, but lower than or equal to 15 wt.% to avoid removing the austenitic phase. In a preferred embodiment, aluminum content is from 6 to 12 wt.%, or even better from 6 to 10 wt.%.
The carbon content is set at 0.5 to 1 .8 wt.%. Carbon plays an important role in the formation of the microstructure of the final part. Its main role is to stabilize austenite which is the main phase of the microstructure of the steel part as well as to provide strengthening. Carbon content below 0.5 wt.% will decrease the proportion of austenite, which leads to the decrease of both ductility and strength of the alloy. However, since it is a main constituent element of the kappa carbide (Fe,Mn)3AICx, a carbon content above 1.8 wt.% can promote the precipitation of such carbides in a coarse manner on the grain boundaries, which results in the decrease of the ductility of the alloy.
Preferably, the carbon content is from 0.6 to 1 .3 wt.%, more preferably from 0.8 to 1 .2% by weight so as to obtain sufficient strength.
Silicon is present in the composition according to the invention at a content from 0 to 0.5 wt.%. It has been observed that the addition of up to 0.5 wt.% of silicon was suppressing hot cracking that occurs when producing the final part by additive manufacturing. However, an addition above 0.5 wt.% leads to cold cracking failure when producing the final part by additive manufacturing. Preferred ranges are from 0.05 to 0.5 wt.%, from 0 to 0.25 wt.% or even better from 0.05 to 0.25 wt.%.
Nickel may be optionally present in a content up to 8.5 wt.%. Nickel can be used as a diffusion barrier to hydrogen. A Nickel amount higher than 8.5 wt.% is not desired because it promotes the formation of cementite in detriment of the (Fe,Mn)3AICx carbides. Nickel can also be used as an effective alloying element because it stabilizes the austenite, and also promotes the formation of ordered compounds in ferrite, such as the B2 component, leading to additional strengthening. However, it is desirable, among others for cost reasons, to limit the nickel addition to a maximum content of 6.0 wt.% or less or 4 wt.% or less and preferably from 0.1 to 2.0 wt.% or from 0.1 to 1 .0 wt.%%. When nickel is not added, the composition may however comprise up to 0.1 wt.% of nickel as an impurity.
Chromium may be optionally present in a content up to 2.5 wt.% for increasing the strength of the steel by solution hardening. It also enhances the high temperature corrosion resistance of the steels according to the invention. However, since chromium reduces the stacking fault energy and the stability of austenite, its content must not exceed 2.5 wt.% and preferably from 0.1 % to 2.0 wt.% or from 0.1 to 1 .0 wt.%. When chromium is not added, the composition may however comprise up to 0.1 wt.% of Cr as an impurity.
Boron may be optionally present in a content up to 0.1 wt%. Boron has a very low solid solubility and a strong tendency to segregate at the grain boundaries, interacting strongly with lattice imperfections. Therefore, boron can be used to limit the precipitation of intergranular kappa carbides.
Tantalum, zirconium, niobium, vanadium, titanium, molybdenum and tungsten are elements that may optionally be used to achieve hardening and strengthening, notably by precipitation of nitrides, carbo-nitrides or carbides. However, when their cumulated amount is above 2.0 wt.%, preferably above 1.0 wt.%, or even better above 0.5 or above 0.3 wt.%, there is a risk that an excessive precipitation may cause a reduction in toughness, which has to be avoided.
The balance is made of iron and unavoidable impurities resulting from the elaboration. Phosphorus, sulfur and nitrogen are the main impurities. They are not deliberately added. They might notably be present in the ferroalloys and/or pure elements used as raw materials. Nitrogen can also be introduced during atomization. Their content is preferably controlled to avoid changing detrimentally the microstructure and/or to avoid increasing the brittleness. Therefore, their content
is respectively limited to 0.013wt.%, to 0.015 wt.% and to 0.1 wt.%. In a preferred embodiment, their content is respectively limited to 0.005 wt.% to 0.015 wt.% and to 0.01 wt.%.
The microstructure of the powder is mainly austenitic and may optionally include up to 1 wt.% of kappa carbides (Fe,Mn)3AICx, up to 1 wt. % of AIN and up to 20 wt.% of ferrite. In a preferred embodiment, the optional ferrite content can be from 0.5 to 10 wt.% or from 0.5 to 5 wt.% or even better from 0.5 to 4.0 wt.%.
The powder can be obtained by first mixing and melting pure elements and/or ferroalloys as raw materials. It can also be obtained by using a pre-alloyed ingot of the required composition.
Ferroalloys refer to various alloys of iron with a high proportion of one or more other elements such as manganese silicon, aluminum, niobium, boron, chromium, molybdenum.... The main alloys are FeMn (usually comprising 70 to 80 wt.% Mn), FeAl (usually comprising 40 to 60 wt.% Al), FeSi (usually comprising 15 to 90 wt.% Si), FeNi (usually comprising 70 to 95 wt.% Ni), FeB (usually comprising 17.5 to 20 wt.% B ), FeCr (usually comprising 50 to 70 wt.% Cr), FeMo (usually comprising 60 to 75 wt.% Mo), FeNb (usually comprising 60 to 70 wt.% Nb), FeV (usually comprising 35 to 85 wt.% V), FeW (usually comprising 70 to 80 wt.% W).
Alloying elements can be alternatively added as pure elements (usually with a purity over 99 wt.%). Pure elements can notably be carbon and pure metals such as iron, aluminum, manganese or nickel, zirconium, titanium, tantalum, molybdenum, tungsten, niobium, vanadium, chromium.
The man skilled in the art knows how to mix different ferroalloys and pure elements to reach a targeted composition.
Once the composition has been obtained by the mixing of the pure elements and/or ferroalloys in appropriate proportions, the composition is heated at a temperature at least 100 °C above its liquidus temperature and maintain at this temperature to melt all the raw materials and homogenize the melt. Thanks to this overheating, the decrease in viscosity of the melted composition helps obtaining a powder with a high sphericity without satellites and with a proper particle size distribution. That said, as the surface tension increases with temperature, it is preferred not to heat the composition at a temperature more than 450 °C above its liquidus temperature.
Preferably, the composition is heated at a temperature at least 200 °C above its liquidus temperature so as to promote the formation of highly spherical particles. More preferably, the composition is heated at a temperature 250 °C above its liquidus temperature.
In one embodiment of the invention, the composition is heated from 1650 to 1800 °C which represents a good compromise between viscosity decrease and surface tension increase.
The molten composition is then atomized into fine metal droplets by forcing a molten metal stream through an orifice, the nozzle, at moderate pressures and by impinging it with jets of gas (gas atomization). The gas is introduced into the metal stream just before it leaves the nozzle, serving to create turbulence as the entrained gas expands (due to heating) and exits into a large collection volume, the atomizing tower. The latter is filled with gas to promote further turbulence of the molten metal jet. The metal droplets cool down during their fall in the atomizing tower. Gas atomization is preferred because it favors the production of powder particles having a high degree of roundness and a low number of satellites.
The atomization gas is preferably argon or nitrogen or a mixture thereof. They both increase the melt viscosity slower than other gases, e.g., helium, which promotes the formation of smaller particle sizes. They also control the purity of the chemistry and play a role in the good morphology of the powder. Finer particles can usually be obtained with argon than with nitrogen since the molar weight of nitrogen is 14.01 g/mole compared with 39.95 g/mole for argon. On the other hand, the specific heat capacity of nitrogen is 1 .04 J/(g K) compared with 0.52 for argon. So, nitrogen increases the cooling rate of the particles. Whenever nitrogen is used as a component of the atomization process, up to 1 weight % of AIN can be formed through the combination of aluminium and nitrogen.
The gas pressure is of importance since it directly impacts the particle size distribution. In particular, the higher the pressure, the higher the cooling rate. Preferably, the gas pressure is set from 10 to 30 bar, or even better from 24 to 30 bar, to promote the formation of particles whose size is most compatible with the additive manufacturing techniques.
The nozzle diameter has an impact on the molten metal flow rate and, thus, on the particle size distribution and on the cooling rate. The nozzle diameter is
preferably limited to 4 mm to limit the increase in mean particle size and the decrease in cooling rate.
The metal powder obtained by atomization can be either used as such or can be sieved to keep the particles whose size better fits the additive manufacturing technique to be used afterwards. For example, in case of additive manufacturing by Powder Bed Fusion, the range 20-63 pm (called fraction F2) is preferred and the range 20-40 pm is even better. In the case of additive manufacturing by Laser Metal Deposition or Direct Metal Deposition, the range 60-150 pm (called F3) is preferred and the range 40-125 pm is even better. Fraction F1 covering particles sizes below 20 pm or even 10 pm can be used for example in binder jetting.
The parts made of the metal powder according to the invention can be obtained by additive manufacturing techniques such as Powder Bed Fusion (LPBF), Direct metal laser sintering (DMLS), Electron beam melting (EBM), Selective heat sintering (SHS), Selective laser sintering (SLS), Laser Metal Deposition (LMD), Direct Metal Deposition (DMD), Direct Metal Laser Melting (DMLM), Direct Metal Printing (DMP), Laser Cladding (LC), Binder Jetting (BJ), Cold Spray (CS), Thermal Spray (TS), High Velocity Oxygen Fuel (HVOF).
In particular, the invention can make use of LPBF process which is a layer- upon-layer additive manufacturing technique. Thin layers of metal powder are evenly distributed using a coating mechanism onto a substrate platform, usually metal, that is fastened to an indexing table that moves in the vertical axis. This takes place inside a chamber containing a tightly controlled atmosphere. Once each layer has been distributed, each 2D slice of the part geometry is fused by selectively melting the powder. This is accomplished with a high-power laser beam, usually an ytterbium fiber laser. The laser energy is intense enough to permit full melting (welding) of the particles in the form of a track or strip. Basically, once a track is done, the process is repeated with the next track, which is separated from the first one by the hatch spacing. The process is repeated layer after layer until the part is complete. The overhanging geometry is supported by nonmelted powder from previous layers. The main process parameters used in LPBF are usually the layer thickness, the hatch spacing, the scan speed and the laser power. After completing the process, the left-over powder is screened to be reused.
The process for producing an additively manufactured part by LPBF comprises a first step of forming a powder layer with the powder according to the invention. Preferably the powder layer is less than 100 pm. Above 100 pm, the laser might not melt the powder in all the layer thickness, which might lead to porosity in the part. Preferably, the layer thickness is kept from 20 to 60 pm to optimize the melting of the powder.
In a second step, a focused laser beam forms a shaped layer by melting at least part of the powder layer in the process conditions detailed below.
In the case of LPBF, each layer of the printed part is at least partially melted in an atmosphere substantially composed of an inert gas.
The laser power is preferably limited to maximum 500 W. Preferably, the laser power is set above 80W to ease the melting in all the layer thickness. In a preferred embodiment, the laser power is from 175 to 300 W.
The scan speed is preferably from 300 to 2000 mm/s and more preferably from 300 to 700 mm/s. Below 300 mm/s, the excess energy provided by the laser might lead key-hole porosity and/or to spatters which, if not properly drag outside of the powder bed, deposit on the powder layer which create voids in the printed part. Above 2000 mm/s, the energy provided by the laser to the powder might not be enough to melt the powder in all the layer thickness.
The Linear Energy Density (LED) is preferably from 190 to 500 J/m. LED is defined as the ratio between the laser power and the scan speed expressed in m/s. Below 190 J/m, LED might not be enough to properly print parts (due to keyholing). Above 400 J/m, the excess energy provided by the laser might lead to spatters which, if not properly drag outside of the powder bed, deposit on the powder layer. Such deposits create voids in the printed part.
The hatch spacing is preferably from 50 to 120 pm. Below 50 pm, each point of the printed part might be remelted multiple times which might lead to overheating. Above 120 pm, non-melted powder might be trapped between two tracks. More preferably, the hatch spacing is from 70 to 110 pm.
The Volumetric Energy Density (VED) is preferably from 100 to 330 J/mm3 VED is defined as P/(v-h- It), where P is the laser power, v is the scan speed, h is the hatch spacing and It is the powder layer thickness.
The invention can alternatively make use of LMD process which is a layer- upon-layer additive manufacturing technique. LMD laser beam forms a melt pool on a metallic substrate, into which powder is fed through a carrier gas. The powder melts under the protection of a shielding gas to form a deposit that is fusion bonded to the substrate. The required geometry is built up in this way, layer by layer thanks to a gantry system or a robotic arm that control both the laser and the powderdelivery nozzle.
The laser power is preferably from 600 to 1000W. Preferably, the laser power is set from 600 to 800W.
The scan speed is preferably from 5 to 40 mm/s and more preferably from 15 to 30 mm/s.
The powder feed rate is preferably from 5 to 40 g/min and more preferably from 10 to 25 g/min.
The layer thickness is preferably from 0.2 to 1.5 mm and more preferably from 0.4 to 1 mm.
The laser spot diameter is preferably from 0.5 to 4 mm and more preferably from 1 to 3 mm. The laser beam shape can be gaussian or top hat.
The carrier gas can be selected among nitrogen, helium or argon or their mixtures and its flow rate is preferably from 2 to 8 l/min and more preferably from 4 to 6 l/min.
The shielding gas can be selected among nitrogen, helium or argon or their mixtures and its flow rate is preferably from 8 to 20 l/min. and more preferably from 10 to 15 l/min.
Depending on the additive manufacturing process used, the microstructure of the parts can be different but are in each case solidification microstructures. Such solidification microstructures are determined by the temperature gradient (G) and growth rate (R) as they involve high cooling rates typical of additive manufacturing methods [Kou, S. (2020). Welding metallurgy. John Wiley & Sons],
As detailed by Agarwal, G. (2019) and shown in figure 2.12 of “Study of Solidification Cracking during Laser Welding in Advanced High Strength Steels. A Combined Experimental and Numerical Approach. Delft University of Technology”, the values of G and R and of the cooling rate define different zones of existence of solidification structures that can be cellular, cellular-dendritric or columnar dendritic.
In the present invention, solidification cellular cells with an equivalent diameter below 2 pm were observed when using LPBF method.
On the contrary, a combination of solidification cells was observed when using LMD method : cellular-dendritic cells with an equivalent diameter below 10 pm and columnar dendritic cells with an equivalent diameter from 10 to 20 pm.
Examples
The following examples and tests presented hereunder are non-restricting in nature and must be considered for purposes of illustration only. They will illustrate the advantageous features of the present invention, the significance of the parameters chosen by inventors after extensive experiments and further establish the properties that can be achieved by the metal powder according to the invention.
Different metal compositions as described in table 1 were first obtained by mixing and melting ferroalloys and pure elements.
P, S and N were respectively maintained below 0.013 wt.%, 0.015 wt.% and 0.1 wt.%.
These metal compositions were heated up to 1800°C, i.e. , 200-350°C above the liquidus temperature, and were then gas atomized with nitrogen in the following process conditions:
- Gas pressure: 20 bar
- Nozzle diameter: 2.5 to 3 mm
The powders are then sieved and classified into F1 to F3 fractions. Their flowability, sphericity and roundness were evaluated and found satisfying for additive manufacturing use. The density of the powders was around 6.9 g/cm3.
Fraction F2
For powders 1 , 2 and 3, the microstructure of the F2 fractions was determined by XRD and gathered in Table 2.
The fraction F2 of such powders was then used to print series of 22 cubes of 1 cm3 by LPBF, using the following parameters:
Laser power from 150 to 200 W,
Scan speed from 300 to 1100 mm/s,
Hatch spacing from 70 to 110 pm
Layer thickness from 20 to 40 pm
Linear Energy Density (LED) from 180 to 500 J/m,
Volumetric Energy Density (VED) from 100 to 330 J/mm3
The cubes were then evaluated, and the corresponding results are gathered in below table 3.
* according to the invention
The printed cubes of trials 3 to 5 exhibited hot cracking. Such cracks were present all along the solidification front in all cubes.
The printed cubes of trials 1 and 2, which are according to the invention, led to cubes without internal cracks.
For powders 1 , 2 and 3, the microstructure of the printed cubes was determined by XRD and gathered in Table 4.
The microstructure of the printed cubes using powder 1 was assessed and shows solidification cellular cells with an equivalent diameter below 2 pm. Such cell sizes were determined by the line intercept method of ASTM E112-10 standard by using transverse SEM micrographs.
The printed cubes corresponding to powder 1 were then submitted to different heating treatments and finally water quenched, to evaluate the evolution of their hardness, measured according to standard ASTM E92-17 for the heating temperatures and times as shown in Table 5.
The evolution of their mechanical properties was also gathered in Table 5, after evaluation using the ASTM standard E8/E8M-16a subsize.
It can be observed that the hardness of the printed cubes is very stable over time, whatever the thermal treatments applied to them. This is also the case for the tensile properties which very stable over temperature and time, when subjected to temperatures up to 500 °C for 4 h.
Similar results showing a good stability were obtained for the toughness of printed cubes corresponding to powder 1 , as measured by Charpy test between 0 and -180°C following ASTM E23-07a standard as gathered in Table 6:
Fraction F3
For powder 1 , the microstructure of the F3 fraction was determined by XRD and gathered in Table 7.
Table 7
according to the invention
The fraction F3 of such powder 1 was then used to print series of prisms of 1 .5 cm3 with LMD technology, using the following parameters:
Laser power from 600 to 800 W,
Scan speed from 15 to 30 mm/s,
Powder feed rate from 10 to 25 g/min
Layer thickness from 0.4 to 1 mm
Laser spot: 1 to 3 mm
Laser beam shape: Gaussian or Top Hat
Carrier gas: N2, He or Ar
Carrier gas flow: from 4 to 6 L/min
Shielding gas: N2, He or Ar
Shielding gas flow: 10 - 15 L/min
The microstructure of the printed cubes was determined by XRD and gathered in Table 8.
The microstructure of the printed cubes using powder 1 was assessed and shows a combination of solidification cells: Cellular-dendritic cells with an equivalent
diameter below 10 m and columnar dendritic cells with an equivalent diameter from 10 to 20 pm. Such cell sizes were determined by the line intercept method of ASTM E112-10 standard by using transverse SEM micrographs. The printed cubes corresponding to powder 1 were then submitted to different isothermal heat treatments and finally water-quenched, to evaluate the evolution of their hardness, measured according to standard ASTM E92-17 for the temperatures and times as shown in Table 9. The evolution of their mechanical properties, as evaluated using the ASTM standard E8/E8M-16a subsize is also gathered in table 9:
Claims
CLAIMS ) Metal powder for additive manufacturing having a composition comprising the following elements, expressed in content by weight:
15% < Mn < 35%
6% < AI < 15%
0.5% < C < 1.8%
0 < Si < 0.5%
P < 0.013%
S < 0.015%
N < 0.100% and optionally containing:
- Ni < 8.5 wt.% and/or Cr < 2.5 wt.% and/or B < 0.1 wt.% and/or one or more elements chosen among Ta, Zr, Nb, V, Ti, Mo, and W in a cumulated amount of up to 2.0 wt.%, the balance being iron and unavoidable impurities resulting from the elaboration, the average particle size of said powder ranking from 1 to 150 pm . ) Metal powder according to claim 1 wherein the powder particles have an austenitic microstructure comprising optionally up to 1 weight % of kappa carbides (Fe,Mn)3AICx, up to 1 weight % of AIN, and up to 20 weight % of ferrite. ) Metal powder according to anyone of claims 1 or 2 wherein the density of said metal powder is below 7.0 g/cm3. ) Metal powder according to anyone of claims 1 to 3 wherein the average particle size ranks from 1 to 20 pm. ) Metal powder according to anyone of claims 1 to 3 wherein the average particle size ranks from 20 to 63 pm.
6) Metal powder according to anyone of claims 1 to 3 wherein the average particle size ranks from 60 to 150 pm.
7) A process for manufacturing a metal powder for additive manufacturing, comprising:
- a) Melting elements and/or metal-alloys at a temperature at least 100 °C above the liquidus temperature to obtain a molten composition according to claim 1 ,
- b) Atomizing the molten composition through a nozzle with a gas pressurized from 10 to 30 bar.
8) A process for manufacturing a printed part by additive manufacturing wherein a powder according to anyone of claims 1 to 6 or obtained according to claim 7 is printed by Laser Powder Bed Fusion.
9) A process according to claim 8, comprising a first step of forming a powder layer with a thickness below 100 pm and a second step where a focused laser beam forms a shaped layer by melting at least part of the powder layer in an atmosphere substantially composed of an inert gas.
10) A process according to anyone of claims 8 or 9 wherein:
- the laser power is limited to maximum 500 W,
- the scan speed is from 300 to 2000 mm/s,
- the Linear Energy Density is from 190 to 500 J/m,
- the hatch spacing is from 50 to 120 pm,
- The Volumetric Energy Density is from 100 to 330 J/mm3.
11 ) A printed part obtained by the process according to anyone of claims 8 to 10 having a cellular solidification structure with an equivalent diameter below 2 pm.
12) A process for manufacturing a printed part by additive manufacturing wherein a powder according to anyone of claims 1 to 7 or obtained according to claim 8 is printed by Laser Metal Deposition.
13) A process according to claim 12, comprising a first step of forming a powder layer with a thickness below 100 pm and a second step where a focused laser beam forms a shaped layer by melting at least part of the powder layer in an atmosphere substantially composed of an inert gas.
14) A process according to anyone of claims 12 or 13 wherein:
- the laser power is from 600 to 1000 W,
- the scan speed is from 5 to 40 mm/s,
- the powder feed rate from 5 to 40 g/min
- the layer thickness from 0.2 to 1 .5 mm
- the laser spot diameter is from 0.5 to 4 mm
- the laser beam shape is Gaussian or Top Hat
- the carrier gas flow is from 2 to 8 L/min
- the shielding gas flow is from 8 to 20 L/min
15) A printed part obtained by the process according to anyone of claims 12 to 14 having a structure made of cellular-dendritic solidification structures with an equivalent diameter below 10 and of columnar dendritic solidification structures with an equivalent diameter from 10 to 20 pm.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/IB2022/060032 WO2024084273A1 (en) | 2022-10-19 | 2022-10-19 | Metal powder for additive manufacturing |
IBPCT/IB2022/060032 | 2022-10-19 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2024084336A1 true WO2024084336A1 (en) | 2024-04-25 |
Family
ID=84246163
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/IB2022/060032 WO2024084273A1 (en) | 2022-10-19 | 2022-10-19 | Metal powder for additive manufacturing |
PCT/IB2023/060222 WO2024084336A1 (en) | 2022-10-19 | 2023-10-11 | Metal powder for additive manufacturing |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/IB2022/060032 WO2024084273A1 (en) | 2022-10-19 | 2022-10-19 | Metal powder for additive manufacturing |
Country Status (1)
Country | Link |
---|---|
WO (2) | WO2024084273A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN118513567A (en) * | 2024-05-22 | 2024-08-20 | 湖南顶立科技股份有限公司 | Rapid heat treatment process for austenitic low-density steel additive manufactured part |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006176843A (en) * | 2004-12-22 | 2006-07-06 | Nippon Steel Corp | High-strength and low-density steel sheet superior in ductility and manufacturing method therefor |
EP3088548A1 (en) * | 2013-12-26 | 2016-11-02 | Posco | Steel sheet having high strength and low density and method of manufacturing same |
WO2017203347A1 (en) * | 2016-05-24 | 2017-11-30 | Arcelormittal | Cold rolled and annealed steel sheet, method of production thereof and use of such steel to produce vehicle parts |
WO2017203345A1 (en) * | 2016-05-24 | 2017-11-30 | Arcelormittal | Cold rolled and annealed steel sheet, method of production thereof and use of such steel to produce vehicle parts |
WO2021123894A1 (en) * | 2019-12-20 | 2021-06-24 | Arcelormittal | Process for the additive manufacturing of maraging steels |
CN113088823A (en) * | 2021-04-08 | 2021-07-09 | 上海富驰高科技股份有限公司 | Light, high-strength and high-corrosion-resistance Fe-Mn-Al-C-Cr steel and preparation method thereof |
EP3851551A1 (en) * | 2020-01-20 | 2021-07-21 | Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG | Metal powder for an additive manufacturing method, uses of the metal powder, method for producing a component and component |
WO2022041819A1 (en) * | 2020-08-25 | 2022-03-03 | 华为技术有限公司 | Fe-mn-al-c lightweight steel and preparation method therefor, terminal, steel structure, and electronic device |
EP4032638A1 (en) * | 2021-01-20 | 2022-07-27 | Sandvik Machining Solutions AB | A steel powder and a method of producing such a powder |
-
2022
- 2022-10-19 WO PCT/IB2022/060032 patent/WO2024084273A1/en unknown
-
2023
- 2023-10-11 WO PCT/IB2023/060222 patent/WO2024084336A1/en unknown
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006176843A (en) * | 2004-12-22 | 2006-07-06 | Nippon Steel Corp | High-strength and low-density steel sheet superior in ductility and manufacturing method therefor |
EP3088548A1 (en) * | 2013-12-26 | 2016-11-02 | Posco | Steel sheet having high strength and low density and method of manufacturing same |
WO2017203347A1 (en) * | 2016-05-24 | 2017-11-30 | Arcelormittal | Cold rolled and annealed steel sheet, method of production thereof and use of such steel to produce vehicle parts |
WO2017203345A1 (en) * | 2016-05-24 | 2017-11-30 | Arcelormittal | Cold rolled and annealed steel sheet, method of production thereof and use of such steel to produce vehicle parts |
WO2021123894A1 (en) * | 2019-12-20 | 2021-06-24 | Arcelormittal | Process for the additive manufacturing of maraging steels |
EP3851551A1 (en) * | 2020-01-20 | 2021-07-21 | Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG | Metal powder for an additive manufacturing method, uses of the metal powder, method for producing a component and component |
WO2022041819A1 (en) * | 2020-08-25 | 2022-03-03 | 华为技术有限公司 | Fe-mn-al-c lightweight steel and preparation method therefor, terminal, steel structure, and electronic device |
EP4032638A1 (en) * | 2021-01-20 | 2022-07-27 | Sandvik Machining Solutions AB | A steel powder and a method of producing such a powder |
CN113088823A (en) * | 2021-04-08 | 2021-07-09 | 上海富驰高科技股份有限公司 | Light, high-strength and high-corrosion-resistance Fe-Mn-Al-C-Cr steel and preparation method thereof |
Non-Patent Citations (1)
Title |
---|
KOU, S: "Welding metallurgy", 2020, JOHN WILEY & SONS |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN118513567A (en) * | 2024-05-22 | 2024-08-20 | 湖南顶立科技股份有限公司 | Rapid heat treatment process for austenitic low-density steel additive manufactured part |
Also Published As
Publication number | Publication date |
---|---|
WO2024084273A1 (en) | 2024-04-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CA2949389C (en) | Layered construction of metallic materials | |
JP7437505B2 (en) | Method for additive manufacturing of maraging steel | |
CN110621796A (en) | Method for manufacturing aluminum alloy parts | |
WO2019139017A1 (en) | Stainless steel powder for molding | |
Lashgari et al. | Additive manufacturing of bulk metallic glasses: Fundamental principle, current/future developments and applications | |
US20230191489A1 (en) | Method for producing an aluminium alloy part | |
CN113412172B (en) | Method for manufacturing aluminum alloy parts | |
KR20220130776A (en) | Powder of cobalt-chromium alloy | |
CA3138382A1 (en) | Steel material and method for manufacturing it | |
EP3371337B1 (en) | Method of layer-by-layer construction of a metallic part | |
WO2024084336A1 (en) | Metal powder for additive manufacturing | |
WO2024084339A1 (en) | Metal powder for additive manufacturing | |
US20230191488A1 (en) | Method for producing an aluminium alloy part | |
JP7503633B2 (en) | Metal Powders for Additive Manufacturing | |
WO2024084335A1 (en) | Metal powder for additive manufacturing | |
JP7503634B2 (en) | Metal Powders for Additive Manufacturing | |
RU2797198C1 (en) | Method for additive manufacturing of maraging steels | |
WO2024224235A1 (en) | Medium manganese powder for additive manufacturing, printed part and method of manufacturing the same | |
RU2806109C1 (en) | Metal powder for additive manufacturing | |
WO2024121595A1 (en) | Metal powder for additive manufacturing | |
WO2023083899A1 (en) | Steel powder for use in additive manufacturing processes | |
BR112022010218B1 (en) | PROCESS FOR MANUFACTURING AN ADDITIVELY MANUFACTURED PART FROM A METAL POWDER | |
CN117597460A (en) | Powder for additive manufacturing, use thereof and additive manufacturing method | |
JP2022035110A (en) | High-strength and high-toughness iron-based alloy, and method for manufacturing the same | |
Esab | Understanding Mechanical Properties of Novel High Strength Steel Weld Metals Through High-Resolution Microstructural Investigations |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 23786778 Country of ref document: EP Kind code of ref document: A1 |