CN105814230B - The method for manufacturing ferrous metal part - Google Patents
The method for manufacturing ferrous metal part Download PDFInfo
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- CN105814230B CN105814230B CN201480067722.7A CN201480067722A CN105814230B CN 105814230 B CN105814230 B CN 105814230B CN 201480067722 A CN201480067722 A CN 201480067722A CN 105814230 B CN105814230 B CN 105814230B
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- axis
- test block
- desiliconization
- demanganize
- grain boundary
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- 238000000034 method Methods 0.000 title claims abstract description 96
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 34
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 title claims abstract description 32
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 28
- 239000002184 metal Substances 0.000 title claims abstract description 28
- 238000012545 processing Methods 0.000 claims abstract description 38
- 239000000463 material Substances 0.000 claims abstract description 17
- 238000005255 carburizing Methods 0.000 claims description 62
- 229910052748 manganese Inorganic materials 0.000 claims description 35
- 229910052710 silicon Inorganic materials 0.000 claims description 34
- 229910052804 chromium Inorganic materials 0.000 claims description 32
- 238000001704 evaporation Methods 0.000 claims description 19
- 230000008020 evaporation Effects 0.000 claims description 19
- 230000015572 biosynthetic process Effects 0.000 claims description 6
- 230000008569 process Effects 0.000 description 78
- 239000007789 gas Substances 0.000 description 62
- 238000012360 testing method Methods 0.000 description 60
- 239000011572 manganese Substances 0.000 description 41
- 230000000052 comparative effect Effects 0.000 description 21
- 238000002474 experimental method Methods 0.000 description 15
- 238000010586 diagram Methods 0.000 description 9
- 230000014759 maintenance of location Effects 0.000 description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- 230000008859 change Effects 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 5
- 238000005259 measurement Methods 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 229910052742 iron Inorganic materials 0.000 description 4
- 238000007517 polishing process Methods 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 238000005242 forging Methods 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 238000010791 quenching Methods 0.000 description 3
- 230000000171 quenching effect Effects 0.000 description 3
- 238000000611 regression analysis Methods 0.000 description 3
- 229910000760 Hardened steel Inorganic materials 0.000 description 2
- VCUFZILGIRCDQQ-KRWDZBQOSA-N N-[[(5S)-2-oxo-3-(2-oxo-3H-1,3-benzoxazol-6-yl)-1,3-oxazolidin-5-yl]methyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C1O[C@H](CN1C1=CC2=C(NC(O2)=O)C=C1)CNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F VCUFZILGIRCDQQ-KRWDZBQOSA-N 0.000 description 2
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- 230000007423 decrease Effects 0.000 description 2
- 238000000295 emission spectrum Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- KRQUFUKTQHISJB-YYADALCUSA-N 2-[(E)-N-[2-(4-chlorophenoxy)propoxy]-C-propylcarbonimidoyl]-3-hydroxy-5-(thian-3-yl)cyclohex-2-en-1-one Chemical compound CCC\C(=N/OCC(C)OC1=CC=C(Cl)C=C1)C1=C(O)CC(CC1=O)C1CCCSC1 KRQUFUKTQHISJB-YYADALCUSA-N 0.000 description 1
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- 229910018663 Mn O Inorganic materials 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 239000000112 cooling gas Substances 0.000 description 1
- 238000005261 decarburization Methods 0.000 description 1
- 235000013399 edible fruits Nutrition 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000009661 fatigue test Methods 0.000 description 1
- 238000005552 hardfacing Methods 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 239000001294 propane Substances 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 238000005480 shot peening Methods 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
- C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
- C23C8/20—Carburising
- C23C8/22—Carburising of ferrous surfaces
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/06—Surface hardening
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
- C21D1/773—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material under reduced pressure or vacuum
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D3/00—Diffusion processes for extraction of non-metals; Furnaces therefor
- C21D3/02—Extraction of non-metals
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/0068—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for particular articles not mentioned below
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/02—Pretreatment of the material to be coated
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
Abstract
A kind of method for manufacturing ferrous metal part, including：Element removal processing is performed to the workpiece formed by ferrous material；And after element removal processing, Surface hardening treatment is performed to workpiece by Carburization Treatment.In the method, element removal processing is performed under conditions of compared with Carburization Treatment higher temperature and lower pressure.
Description
Technical field
The present invention relates to a kind of method for making metallic hardfacing manufacture ferrous metal part using Carburization Treatment, and especially
It is related to a kind of technology of brittleness oxydic layer of grain boundary for suitably reducing during Carburization Treatment and being formed on metal surface.
Background technology
For example, in the ferrous metal part for making such as steel part as main component comprising Fe, it is known that one kind is for example, by gas
Carbon is embedded in metal surface and then the technology by quenching the hardness to enhance metal surface by Carburization Treatment.For example, Japan is specially
Profit application discloses 05-171348 (JP 05-171348 A) number and discloses this ferrous metal part.
However, in JP 05-171348 A, it is known that the oxygen included in carburizing gas during gas carburizing processing
Penetrate into ferrous metal part material surface crystal boundary and by with material surface included in such as Si, Mn or Cr element knot
Conjunction forms brittleness oxydic layer of grain boundary.In order to handle it, in JP 05-171348 A, wrapped by reducing in ferrous metal part
The content of Si, Mn or Cr for containing reduce the formation of oxydic layer of grain boundary.
Invention content
Ferrous metal part disclosed in JP 05-171348 A has the office of the content for the element for reducing such as Si, Mn or Cr
It is sex-limited, thus its problem is the crystal boundary oxygen that the element of such as Si, Mn or Cr that the surface because of ferrous metal part is included are formed
Change layer and make the decrease of fatigue strength of ferrous metal part.
The present invention provides a kind of methods for manufacturing ferrous metal part, and this method can be by suitably reducing in Carburization Treatment
The oxydic layer of grain boundary that period is formed improves fatigue strength.
Due to various analyses and investigation, inventor has discovered that following facts.That is, find the member of such as Si, Mn or Cr
Element evaporation, that is, the surface for the workpiece that ferrous material is formed under conditions of compared with Carburization Treatment higher temperature and lower pressure
Element removal phenomenon has occurred.Moreover, usually element removal phenomenon has such as the negative impression in the case of " decarburization ".However,
On the contrary, it finds by being sent out based on the technological know-how in relation to carburizing the element to be made to remove phenomenon before carrying out Carburization Treatment
It is raw, it can suitably inhibit the formation of oxydic layer of grain boundary in subsequent Carburization Treatment.The present invention have been based on above-mentioned discovery and
It makes.
A kind of method of manufacture ferrous metal part of scheme according to the present invention includes：The workpiece formed to ferrous material is held
Row element removal is handled；And after element removal processing, Surface hardening treatment is performed to workpiece by Carburization Treatment.At this
In method, element removal processing is performed under conditions of compared with Carburization Treatment higher temperature and lower pressure.
In the method according to the manufacture ferrous metal part of the program, element removal processing is compared with Carburization Treatment higher temperature
And performed under conditions of lower pressure.Therefore, before Carburization Treatment, the member of oxide formation is caused during Carburization Treatment
Element is by the surface evaporation from workpiece.It therefore, can be by the oxydic layer of grain boundary formed on the surface of workpiece during Carburization Treatment
It suitably removes, and the fatigue strength of ferrous metal part can improve.
According to the program, in element removal processing, before Carburization Treatment, on workpiece surface during Carburization Treatment
The element for forming oxide can be by the surface evaporation from workpiece.Therefore, it is formed during Carburization Treatment on the surface of workpiece
Oxydic layer of grain boundary can be properly removed.
According to the program, in element removal processing, element can be in a vacuum by the surface evaporation from workpiece.Therefore,
It can be properly removed in the oxydic layer of grain boundary formed on the surface of workpiece during Carburization Treatment.
According to the program, element can be at least one of Mn, Si and Cr.Therefore, in element removal processing, have
At least one of Mn, Si and Cr of relatively high steam pressure are by the surface evaporation from workpiece.Therefore, during Carburization Treatment
It can be properly removed in the oxydic layer of grain boundary formed on the surface of workpiece.
According to the program, after element removal processing, the higher temperature of element removal processing can be down to Carburization Treatment
Temperature to perform Carburization Treatment.Therefore, after element removal processing, Carburization Treatment can be persistently appropriately performed.
Description of the drawings
It is important to describe the feature of exemplary embodiment of the present invention, advantage and technology and industry below with reference to accompanying drawings
Property, wherein, identical label represents identical element, and wherein：
Fig. 1 is to show to be used for using the axis and showing manufactured by the method for manufacture ferrous metal part according to the present invention
Manufacture the schematic diagram of the configuration of the device of the axis；
Fig. 2 is the flow chart of the manufacturing process for the axis for showing Fig. 1；
Fig. 3 is to show desiliconization demanganize process shown in Fig. 2 and temperature condition and pressure strip in Gas Carburizing Process
The schematic diagram of part；
Fig. 4 is to show experiment I as a result, the survey formed in experiment I by using the material identical with the axis of Fig. 1
Test specimen, in different temperature (DEG C), pressure (Pa) and under conditions of the retention time (min) during the desiliconization demanganize of Fig. 2
Measure the content (mass percent) of Si, Mn and Cr included in the surface of test block；
Fig. 5 is to show Mn and Si that the surface of the test block formed by the material identical with the axis of Fig. 1 is included
The schematic diagram of content, the test block include the test block (root manufactured by the desiliconization demanganize process and Gas Carburizing Process of Fig. 2
According to the axis of example 1) and the test block that is only manufactured by the Gas Carburizing Process of Fig. 2 (according to the axis of comparative example 1)；
Fig. 6 is shown in the test block (according to the axis of example 1) and test block (according to the axis of comparative example 1) of Fig. 5
The schematic diagram of the thickness of the oxydic layer of grain boundary of formation；
Fig. 7 is the schematic diagram of the part surface for the test block (according to the axis of comparative example 1) for showing Fig. 5；
Fig. 8 is the schematic diagram of the part surface for the test block (according to the axis of example 1) for showing Fig. 5；
Fig. 9 be show Fig. 5 test block (according to the axis of example 1) and test block (according to the axis of comparative example 1) it is tired
The schematic diagram of labor intensity；And
Figure 10 is schematic diagram corresponding with Fig. 1, and it illustrates the manufacturers according to another exemplary ferrous metal part of the present invention
Method.
Specific embodiment
The example 1 of the present invention is described below in reference to attached drawing.In the attached drawing of example 1 below, suitably simplify and change
Into per part, its size, shape etc. may not be illustrated accurately.
Fig. 1 is to show the schematic diagram of ferrous metal part that the present invention is suitably applied to, i.e., for example including making in the car
Axis 10 in variable v-belt drive (CVT).Axis 10 is formed by making ferrous material as main component comprising Fe, example
Such as, it is formed by the steel of C content such as with 0.02% to 2.14% (wt%) or the mild steel of case-hardened steel.The table of axis 10
Face carries out carburizing by the gas carburizing system 12 of Fig. 1；Therefore make the Surface hardened layer.
Gas carburizing system 12 will be described herein.As shown in Figure 1, gas carburizing system 12 includes：Thermal processing chamber 16,
It is formed by heat insulator 14 and accommodates axis 10；Fixture 18, the fixed and support shaft 10 in thermal processing chamber 16；Heater
20, heat the inside of thermal processing chamber 16；Mass flow controller 24 measures and the supply from supply such as nitrogen is controlled to set
Standby 22 are flowed into the flow of the nitrogen in thermal processing chamber 16；And drawdown pump 26, to the internal air exhausting of thermal processing chamber 16
To reduce the internal pressure of thermal processing chamber 16.Therefore, in gas carburizing system 12, axis 10 can be in thermal processing chamber 16
Relatively-high temperature and relatively low pressure are maintained at by heater 20 included in gas carburizing system 12 and drawdown pump 26
Under the conditions of.In addition, the temperature of axis 10 is cooled down by being used as the nitrogen of the cooling gas supplied from supply arrangement 22, so as to cool down
Axis 10.In addition, gas carburizing system 12 is equipped with carburizing gas supply arrangement (not shown), which will ooze
Carbon gas is supplied to thermal processing chamber 16.During gas carburizing processing, it is continually provided and oozes from carburizing gas supply arrangement
Carbon gas.Carburizing gas for example, by will the source gas body such as propane flammable gas, town gas, natural gas or wood gas and air with pre-
Fixed ratio mixes and is heated to decomposing to prepare by the mixed gas.
In addition, will the method that axis 10 is manufactured according to example 1, i.e. manufacturing process P1 to P5 be described using Fig. 2 herein.
As shown in Fig. 2, first, it, will be for example as case-hardened steel for example, by forging in forging process P1
The component shaping that the ferrous material (Steel material) of SCR420 is formed is predetermined shape.
Then, in (annealing) process P2 is preheated, the workpiece formed in forging process P1 is annealed and is softened.
Then, in mechanical processing process P3, the workpiece softened in warm P2 is cut by being machined
The shape identical with axis 10.
Then, in desiliconization demanganize (element removal) process P4, as the workpiece cut in mechanical processing process P3
Axis 10 be arranged in gas carburizing system 12 and be maintained at than Gas Carburizing Process described below (carburizing process) P5 temperature
Higher and pressure it is lower under conditions of continue scheduled time t (min), for example, in the internal temperature T (DEG C) of thermal processing chamber 16
For 1000 DEG C to 1300 DEG C and vacuum, i.e. the internal pressure P (Pa) of thermal processing chamber 16 is the condition of 100Pa to 1000Pa
Under, the scheduled time t is, for example, 5 minutes to 30 minutes.Therefore, evaporated such as Mn included in the surface of axis 10,
The element with relatively high steam pressure of Si or Cr.In desiliconization demanganize process P4, vacuum is represented compared with atmospheric pressure
Sufficiently low pressure, for example, about 100Pa are to 1000Pa.The pressure P (100Pa to 1000Pa) of desiliconization demanganize process P4 is compared with for example
It is sufficiently low for the pressure condition (higher than 1KPa and below 10KPa) of the vacuum carburization processing of the prior art.
Then, in Gas Carburizing Process P5, by a temperature of about 930 DEG C of gas carburizing as shown in Figure 3
Carburizing gas, carbon is embedded in the surface of axis 10, the axis 10 with such as Mn, Si or Cr element in desiliconization demanganize process
From the surface of its evaporation in P4.Then, carburizing axis 10 is hastily cooled down and is quenched.Therefore, the surface by being hardened is produced
And improve the axis 10 of fatigue strength.In gas carburizing system 12, as shown in figure 3, after desiliconization demanganize process P4, temperature
Such as about 930 DEG C of gas carburizing temperature is down to perform Gas Carburizing Process P5.In addition, in the inside of thermal processing chamber 16
Pressure is about 1.0 × 105Pa performs Gas Carburizing Process P5 under atmospheric pressure that is, shown in Fig. 3.
Other than the mechanism of carburizing and quenching is carried out to axis 10, gas carburizing system 12 further includes makes heat before carburization
The inside of processing chamber housing 16 is maintained at the mechanism under high temperature and low pressure (vacuum).Therefore, the manufacturing process P1 of example 1 is being performed extremely
During P5, i.e., when performing desiliconization demanganize process P4 and Gas Carburizing Process P5, in addition to the prior art carries out carburizing to axis 10
Except the gas carburizing system of quenching, it is not necessary that for example in desiliconization demanganize process P4 addition make axis 10 be maintained at high temperature and
New equipment under low-pressure state.Therefore, manufacture cost can be significantly reduced.
[experiment I]
The experiment I for the present inventor will be described being carried out herein.Carry out experiment I with prove the Si of the surface evaporation from axis 10,
The fact that amount of Mn and Cr can suitably increase, that is, can be by changing temperature T (DEG C), pressure in desiliconization demanganize process P4
Power P (Pa) and retention time t (min) suitably reduces the content of Si, Mn and Cr included in the surface of axis 10.
In I is tested, under the conditions of 16 kinds, i.e., in condition 1 to 16 times execution desiliconization demanganize process P4 of condition, wherein：It adopts
With by the material identical with axis 10, i.e. SCR420 is formed and is had the test block of predetermined shape (for example, Ф 18mm × 50mm)；Temperature
Degree T (DEG C) change in the range of 1000 DEG C to 1300 DEG C as shown in Figure 4, i.e. temperature T (DEG C) for 1000 DEG C, 1100 DEG C, 1200
DEG C or 1300 DEG C；Pressure P (Pa) changes in the range of 100Pa to 1000Pa, i.e. pressure P (Pa) for 100Pa, 200Pa,
500Pa or 1000Pa；And retention time t (min) changed in the range of 5 minutes to 30 minutes, i.e. retention time t (min) is 5
Minute, 10 minutes, 15 minutes or 30 minutes.Measure corresponding to axis 10 test block on it under condition 1 to condition 16
Perform the content of Si, Mn and Cr in the surface of desiliconization demanganize process P4.
In I is tested, as shown in figure 5, the per unit mass of the depth on 6 μm of the surface away from the test block corresponding to axis 10
10 times of Si contents (mass percent), Mn contents (mass percent) and Cr contents (mass percent) and (10Si+Mn
+ Cr) it is represented by the content y (mass percent) of Si, Mn and Cr in the surface for the test block for corresponding to axis 10.In addition, away from right
Aura should be passed through in the content (mass percent) of Si, Mn and Cr of the per unit mass of the depth on 6 μm of the surface of test block
Emission spectrum discharge to measure.
Fig. 4 be will hereinafter use to describe the result of experiment I.As shown in figure 4, the content y (matter of Si, Mn and Cr of test block
Measure percentage) condition 8, condition 9 and condition 13 time be relatively small 2 (mass percents) below.It is therefore contemplated that pass through
In condition 8, condition 9 and the execution desiliconization demanganize process P4 of condition 13 times, can suitably reduce the Si included in the surface of axis 10,
The content y (mass percent) of Mn and Cr.
In addition, the experimental result by using condition 1 shown in Fig. 4 to condition 16 carries out multiple regression analysis, obtain
Temperature T (DEG C), pressure P (Pa) and retention time t (min) in desiliconization demanganize process P4 and the test block corresponding to axis 10
Relational expression (1) between the content y (mass percent) of Si, Mn and Cr in surface.Y (mass percent)=-
0.0018×T(℃)+0.0001×P(Pa)-0.0242×t(min)+6.47677…(1)
From relational expression (1) as can be seen that in desiliconization demanganize process P4, suitably made by increasing temperature T (DEG C)
The element of such as Si, Mn or Cr suitably make such as Si, Mn or Cr from the surface evaporation of axis 10 by reducing pressure P (Pa)
Element from the surface evaporation of axis 10, and by increase retention time t (min) suitably make the element of such as Si, Mn or Cr from
The surface evaporation of axis 10.In general, when the content y (mass percent) of Si, Mn and Cr in the surface of axis 10 are 2 (quality percentages
Than) below when, the thickness of oxydic layer of grain boundary A (with reference to Fig. 7) formed on the surface by Carburization Treatment can be suppressed in 6.0
μm hereinafter, can thus inhibit the decline of fatigue strength.It is therefore contemplated that for example by setting the temperature in desiliconization demanganize process P4
T (DEG C), pressure P (Pa) and retention time t (min) make the content y (mass percent) of Si, Mn and Cr in the surface of axis 10 be
2 (mass percents) are hereinafter, can suitably inhibit in Gas Carburizing Process P5 in the crystal boundary oxygen formed on the surface of axis 10
Change layer A.
[experiment II]
To the experiment II that carried out by the present inventor be described herein.Experiment II is carried out to prove the manufacturing process P1 to P5 of Fig. 2
Influences of the middle desiliconization demanganize process P4 to axis, i.e. desiliconization demanganize process P4 is to the oxydic layer of grain boundary A's that is formed on the surface of axis 10
It influences.In II is tested, the influence of the oxydic layer of grain boundary A that is formed on axis 10 to the fatigue strength of axis 10 is also demonstrated.
It in II is tested, measures and is formed by the material identical with axis 10, i.e., formed by SCR420 and there is preboarding
The thickness (μm) of oxydic layer of grain boundary A formed on the test block of shape (for example, Ф 18mm × 50mm), the test block include：With root
According to the 10 corresponding test block of axis (desiliconization demanganize+gas carburizing) of example 1, wherein performing desiliconization demanganize on the test block
Journey P4 and Gas Carburizing Process P5；And with the 10 corresponding test block (only gas carburizing) of axis according to comparative example 1, wherein
Gas Carburizing Process P5 is only performed on the test block without performing desiliconization demanganize process P4.In addition, measuring and according to example 1
10 corresponding test block of axis and fatigue strength with the 10 corresponding test block of axis according to comparative example 1, i.e. nominal stress σ
(MPa).In desiliconization demanganize process P4, in 8 times execution element removal processing of condition as escribed above.In addition, in II is tested,
It is prepared for by the material identical with axis 10, i.e. SCR420 is formed and had the survey of scheduled shape (for example, Ф 18mm × 50mm)
Test specimen only performs the test block Gas Carburizing Process P5 without performing desiliconization demanganize process P4, and the test block is held
The polishing process gone by being machined the surface to remove test block, i.e. oxydic layer of grain boundary A.Therefore, be prepared for according to than
Compared with the 10 corresponding test block of axis (gas carburizing+polishing) of example 2.Utilize the survey corresponding with the axis 10 according to comparative example 2
Test specimen measures fatigue strength.
The result for hereafter experiment II being described using Fig. 5 and Fig. 9.As shown in figure 5, in test block (according to the axis of example 1
10) in, compared to test block (according to the axis 10 of comparative example 1), suitably reduce Si included in the surface of test block
With the content (mass percent) of Mn.Fig. 5 shows the result of the above-mentioned measurement using glow discharge emission spectrum.
In addition, as shown in fig. 6, the thickness of the oxydic layer of grain boundary A formed in test block (according to the axis 10 of example 1) is 4 μ
The thickness of m, the oxydic layer of grain boundary A formed in test block (according to the axis 10 of comparative example 1) are 20 μm.Test block (according to
The axis 10 of example 1) in, compared to test block (according to the axis 10 of comparative example 1), suitably reduce oxydic layer of grain boundary A.Pass through
Surface and the test block of the test block (according to the axis 10 of example 1) shown in such as Fig. 7 and Fig. 8 are measured using light microscope
The oxydic layer of grain boundary on the surface of (according to the axis 10 of comparative example 1) obtains the measured value of the thickness of the oxydic layer of grain boundary A of Fig. 6.
The thickness of oxydic layer of grain boundary A is defined as the depth on the surface for observing grain boundaries away from test block.In fig. 8, it does not observe
Oxydic layer of grain boundary A.
In addition, as shown in figure 9, when number of repetition Nf is about 107When, the nominal of test block (according to the axis 10 of example 1)
Stress σ is about 580MPa, and the nominal stress σ of test block (according to the axis 10 of comparative example 2) is about 575MPa, and test block
The nominal stress σ of (according to the axis 10 of comparative example 1) is about 515MPa.Therefore, with the 10 corresponding test of axis according to example 1
The fatigue strength of part is suitably higher than the fatigue strength with the 10 corresponding test block of axis according to comparative example 1.The measurement knot of Fig. 9
Fruit is obtained using for example small wild formula rotary bending fatigue test device.
According to experiment II's as a result, as shown in the measurement result of Fig. 5, it is corresponding with the axis 10 according to example 1, hold on it
Gone in the test block of desiliconization demanganize process P4, it is corresponding compared to the axis 10 according to comparative example 1, do not perform on it is de-
The test block of silicon demanganize process P4, the Si and the content (mass percent) of Mn included in test block surface are suitably subtracted
It is few.It is therefore contemplated that Si that oxide (SiO, MnO) formed on the surface of axis 10 and Mn is caused to lead in Gas Carburizing Process P5
Cross desiliconization demanganize process P4 and from the surface evaporation of axis 10.
In addition, according to experiment II's as a result, as shown in the measurement result of Fig. 5 and Fig. 6, right with the axis 10 according to example 1
In test block answering, performing desiliconization demanganize process P4 on it, corresponding compared to the axis 10 according to comparative example 1,
The test block of desiliconization demanganize process P4 is not performed on it, the Si and the content of Mn included in test block surface is suitably subtracted
It is few, and the thickness of oxydic layer of grain boundary A formed in test block is adaptively reduced.It is therefore contemplated that by desiliconization demanganize
Si and Mn is suitably reduced into the content of the Si and Mn in 10 surface of axis, and subtract from the surface evaporation of axis 10 in process P4
The amount included in carburizing gas and in subsequent gases carburizing process P5 with Si and the Mn O combined is lacked, so as to reduce
The oxydic layer of grain boundary A formed on axis 10.
In addition, according to experiment II's as a result, as shown in the measurement result of Fig. 6 and Fig. 9, it is corresponding with the axis 10 according to example 1
Test block fatigue strength higher than fatigue strength with the 10 corresponding test block of axis according to comparative example 1, wherein described
In example 1, the thickness of oxydic layer of grain boundary A is relatively thin (4 μm), in the comparative example 1, the thickness phase of oxydic layer of grain boundary A
To thicker (20 μm).Show in addition, being higher than with the fatigue strength of the 10 corresponding test block of axis according to comparative example 2 with compared with
The fatigue strength of the 10 corresponding test block of axis of example 1 wherein in the comparative example 2, is not carried out desiliconization demanganize process P4
And oxydic layer of grain boundary A is eliminated by polishing process.It is therefore contemplated that by reducing the oxydic layer of grain boundary A's formed on axis 10
Thickness improves the fatigue strength of axis 10.Additionally it is believed that in the manufacturing process according to the axis 10 of example 1, pair with compared with
The 10 corresponding test block of axis of example 2 perform by being machined in the polishing process to remove oxydic layer of grain boundary A, be manufactured into
This is than the manufacture cost higher of desiliconization demanganize process P4.It is therefore contemplated that in the manufacturing process P1 to P5 of the axis 10 according to example 1
In, perform the manufacture of the axis 10 according to comparative example 2 of polishing process compared to desiliconization demanganize process P4 is not carried out
Journey suitably reduces manufacture cost.
In the manufacturing process P1 to P5 according to the axis 10 of example 1, before Gas Carburizing Process P5, compared with gas carburizing
Process P5 temperature higher and pressure it is lower under conditions of perform desiliconization demanganize process P4.Therefore, before Gas Carburizing Process P5,
Cause surface evaporation of the element of such as Si, Mn and Cr that oxide is formed from axis 10 in Gas Carburizing Process P5.Therefore, may be used
Suitably to reduce the oxydic layer of grain boundary A formed on the surface of axis 10 during Gas Carburizing Process P5, so as to improve
The fatigue strength of axis 10.
In addition, in the manufacturing process P1 to P5 according to the axis 10 of example 1, the desiliconization before Gas Carburizing Process P5 takes off
In manganese process P4, such as Si, Mn or Cr that oxide is formed on the surface of axis 10 are caused during Gas Carburizing Process P5
Element is from the surface evaporation of axis 10.Therefore, the shape on the surface of axis 10 can suitably be reduced during Gas Carburizing Process P5
Into oxydic layer of grain boundary A.
In addition, in the manufacturing process P1 to P5 according to the axis 10 of example 1, in desiliconization demanganize process P4, in pressure foot
In enough subatmospheric vacuum, i.e., under the pressure of 100Pa to 1000Pa, cause oxide during Gas Carburizing Process P5
The element of such as Si, Mn or Cr on the surface of axis 10 are formed in from the surface evaporation of axis 10.Therefore, it can suitably reduce
The oxydic layer of grain boundary A formed on the surface of axis 10 during Gas Carburizing Process P5, so as to improve the fatigue strength of axis 10.
In addition, in the manufacturing process P1 to P5 according to the axis 10 of example 1, oxidation is caused during Gas Carburizing Process P5
The element that object is formed is Mn, Si or Cr.Therefore, in desiliconization demanganize process P4, such as Mn, Si or Cr's has relatively high steam
The element of pressure is from the surface evaporation of axis 10.Therefore, it can suitably reduce during Gas Carburizing Process P5 in the table of axis 10
The oxydic layer of grain boundary A formed on face.
In addition, in the manufacturing process P1 to P5 according to the axis 10 of example 1, after desiliconization demanganize process P4, temperature drop
To the temperature of about 930 DEG C of Gas Carburizing Process P5 to perform Gas Carburizing Process P5.Therefore, desiliconization demanganize process P4 it
After can continue to be appropriately performed Gas Carburizing Process P5.
Another example of the present invention is described below.In the following description, the component identical with above-mentioned example 1 is by phase
Same reference number represents, it will not be repeated to describe.
According to the manufacturing process and manufacturing process P1 to the P5 substantially phases of the axis 10 according to example 1 of this exemplary ferrous metal part
Together, in addition to gear 28 of the manufacture as the driving part used in such as vehicle rather than the axis 10 according to example 1.According to Figure 10
The shape of shown exemplary gas carburizing system 12 and the gas carburizing system 12 of example 1 according to figure 1 is slightly different.
For example, there are different shapes according to this exemplary heater 20 and fixture 18 and example 1 but it is identical with example 1.
It is similar with the effect of above-mentioned example 1 in the manufacturing process according to exemplary gear 28, in desiliconization demanganize process P4
In, the oxydic layer of grain boundary A formed on the surface of gear 28 during Gas Carburizing Process P5 can be suitably reduced, so as to
To improve the fatigue strength of gear 28.In addition, in order to manufacture gear 28, the peening for improving fatigue strength is usually performed
Process.But in the manufacturing process according to this exemplary gear 28, due to suitably improving fatigue strength, so shot-peening
Hardening process is unnecessary.Therefore, the manufacture cost of gear 28 can greatly be reduced.
More than, example of the invention is described with reference to attached drawing, but the present disclosure additionally applies for other embodiments.
In the manufacturing process P1 to P5 according to exemplary axis 10, in desiliconization demanganize process P4, such as Mn, Si or Cr's
Element with opposite vapor pressure is suitably evaporated from the surface of axis 10.But other elements can also be from the table of axis 10
It is evaporated on face.In addition, by least one of surface evaporation Mn, Si and Cr from axis 10 elements, grain boundary oxidation can be inhibited
The formation of layer A, so as to improve the fatigue strength of axis 10.
In addition, in the manufacturing process P1 to P5 according to exemplary axis 10, in desiliconization demanganize process P4, by using figure
The result of experiment I shown in 4 carries out multiple regression analysis, obtains temperature T (DEG C) in desiliconization demanganize process P4, pressure
Relationship between the content y (mass percent) of P (Pa) and Si, Mn and Cr in the surface of retention time t (min) and axis 10
Expression formula (1).However, for example, when the material of axis 10 becomes another kind from SCR420, it can be by using identical with the example
Method later carry out multiple regression analysis carry out experiment I and obtain new relational expression.
In addition, in the examples described above, axis 10 and gear 28 used in vehicle are used as the example of ferrous metal part.However,
The present disclosure additionally applies for other ferrous metal parts.That is, the present invention is suitable for performing it any ferrous metal part of Carburization Treatment.This
Outside, in the examples described above, axis 10, i.e. ferrous metal part are formed by making ferrous material as main component comprising Fe, for example, by
Steel material with C content for 0.02% to 2.14% (weight percent) is formed.However, ferrous metal part can be by containing with C
The pure iron of less than 0.02% amount is formed.
Above-mentioned example is only exemplary, and the knowledge based on those skilled in the art can be that the present invention increases various repair
Change and improve.
Claims (3)
1. a kind of method for manufacturing ferrous metal part, the method are characterized in that including：
Element removal processing is performed to the workpiece formed by ferrous material, wherein in element removal processing, in carburizing
In the element of formation oxide on the surface of the workpiece by the surface evaporation from the workpiece during processing；And
After element removal processing, Surface hardening treatment is performed to the workpiece by Carburization Treatment, wherein
The element removal processing is performed under conditions of the Carburization Treatment higher temperature and lower pressure,
The element is at least one of Mn, Si and Cr.
2. according to the method described in claim 1, it is characterized in that
In element removal processing, the element is in a vacuum by the surface evaporation from the workpiece.
3. method according to claim 1 or 2, it is characterised in that
After element removal processing, the temperature of element removal processing be down to the temperature of the Carburization Treatment with
Perform the Carburization Treatment.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2013257520A JP6171910B2 (en) | 2013-12-12 | 2013-12-12 | Manufacturing method of ferrous metal parts |
| JP2013-257520 | 2013-12-12 | ||
| PCT/IB2014/002806 WO2015087154A1 (en) | 2013-12-12 | 2014-12-08 | Method of manufacturing ferrous metal component |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105814230A CN105814230A (en) | 2016-07-27 |
| CN105814230B true CN105814230B (en) | 2018-06-19 |
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ID=52273362
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201480067722.7A Expired - Fee Related CN105814230B (en) | 2013-12-12 | 2014-12-08 | The method for manufacturing ferrous metal part |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US20160305007A1 (en) |
| JP (1) | JP6171910B2 (en) |
| CN (1) | CN105814230B (en) |
| DE (1) | DE112014005676T5 (en) |
| WO (1) | WO2015087154A1 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6520547B2 (en) * | 2015-08-10 | 2019-05-29 | 日本製鉄株式会社 | Method of manufacturing test piece |
| EP3502302B1 (en) | 2017-12-22 | 2022-03-02 | Ge Avio S.r.l. | Nitriding process for carburizing ferrium steels |
Family Cites Families (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61163202A (en) * | 1985-01-11 | 1986-07-23 | Nippon Steel Corp | Method for continuous desiliconization and desulfurization of molten iron |
| JPS61243104A (en) * | 1985-04-17 | 1986-10-29 | Nippon Jiryoku Senko Kk | Method for producing steel shot material |
| JPS63145701A (en) * | 1986-12-08 | 1988-06-17 | Toyota Motor Corp | Method for sintering stainless steel powder |
| JPH05171348A (en) | 1991-12-20 | 1993-07-09 | Aichi Steel Works Ltd | Carburizing steel excellent in impact fatigue strength |
| JPH0853711A (en) * | 1994-08-11 | 1996-02-27 | Kobe Steel Ltd | Surface hardening treating method |
| TW336257B (en) * | 1996-01-30 | 1998-07-11 | Daido Hoxan Inc | A method of carburizing austenitic stainless steel and austenitic stainless steel products obtained thereby |
| JPH09302454A (en) * | 1996-05-13 | 1997-11-25 | Toyota Central Res & Dev Lab Inc | Pre-treatment of carburizing quenched material and manufacture thereof |
| JP3486506B2 (en) * | 1996-06-03 | 2004-01-13 | 光洋精工株式会社 | Gas carburizing method |
| CN1203959A (en) * | 1997-04-29 | 1999-01-06 | 奥瓦科钢铁股份公司 | Case hardening steel |
| JP3442737B2 (en) * | 2000-12-11 | 2003-09-02 | 中外炉工業株式会社 | Vacuum carburizing method for steel parts containing Cr and / or Mn |
| EP1396621B1 (en) * | 2001-05-10 | 2015-09-09 | Akita Fine Blanking Co., Ltd. | Surface-reformed exhaust gas guide assembly of vgs type turbo charger, and method of surface-reforming component member thereof |
| WO2006118242A1 (en) * | 2005-04-28 | 2006-11-09 | Aisin Aw Co., Ltd. | Steel member and process for heat treatment thereof |
| JP4327781B2 (en) * | 2005-09-12 | 2009-09-09 | Ｎｔｎ株式会社 | Manufacturing method of carburized parts |
| US20120251377A1 (en) * | 2011-03-29 | 2012-10-04 | Kuen-Shyang Hwang | Method for enhancing strength and hardness of powder metallurgy stainless steel |
| CN102352478B (en) * | 2011-10-31 | 2013-02-20 | 北京机电研究所 | Automatic telescopic carburizing gas nozzle device of vacuum low pressure carburizing device |
-
2013
- 2013-12-12 JP JP2013257520A patent/JP6171910B2/en not_active Expired - Fee Related
-
2014
- 2014-12-08 CN CN201480067722.7A patent/CN105814230B/en not_active Expired - Fee Related
- 2014-12-08 WO PCT/IB2014/002806 patent/WO2015087154A1/en active Application Filing
- 2014-12-08 US US15/103,660 patent/US20160305007A1/en not_active Abandoned
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| Publication number | Publication date |
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| DE112014005676T5 (en) | 2016-10-06 |
| JP2015113509A (en) | 2015-06-22 |
| US20160305007A1 (en) | 2016-10-20 |
| JP6171910B2 (en) | 2017-08-02 |
| WO2015087154A1 (en) | 2015-06-18 |
| CN105814230A (en) | 2016-07-27 |
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