CN108677136A - A method of eliminating hard alloy decarburization defect - Google Patents
A method of eliminating hard alloy decarburization defect Download PDFInfo
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- CN108677136A CN108677136A CN201810523506.9A CN201810523506A CN108677136A CN 108677136 A CN108677136 A CN 108677136A CN 201810523506 A CN201810523506 A CN 201810523506A CN 108677136 A CN108677136 A CN 108677136A
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- decarburization
- hard alloy
- coating
- titanium dioxide
- carbon black
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- 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
- C23C8/40—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 liquids, e.g. salt baths, liquid suspensions
- C23C8/42—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 liquids, e.g. salt baths, liquid suspensions only one element being applied
- C23C8/44—Carburising
-
- 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
- C21D3/04—Decarburising
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/16—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of other metals or alloys based thereon
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Powder Metallurgy (AREA)
Abstract
The invention discloses a kind of methods for eliminating hard alloy decarburization defect, belong to the manufacture production field of hard alloy, including：Titanium dioxide, carbon black and solvent are configured to coating；Then coating is uniformly applied to carbide surface, carries out decarburization and returns burning；Hard alloy after burning is returned to decarburization and carries out blasting treatment.Coating is covered decarburization position by the present invention and qualified position is not smeared, and selectively can be carried out decarburization to decarburization position and be returned burning；It after coating material is covered in product surface, can be directly placed on the graphite boat of original carrying product, no special boat requirement；It carries out returning burning using vacuum sintering furnace or low-pressure sintering furnace, paste coating is vacuumized in sintering process, will not distribute pollution sintering furnace and its pipeline, is not needed any cleaning or is used special sintering furnace；This method for eliminating hard alloy decarburization defect provided by the invention, realizes the elimination of hard alloy decarburization defect, process is short, and production cost is low.
Description
Technical field
The invention belongs to the manufacture production fields of hard alloy, and in particular to a kind of side eliminating hard alloy decarburization defect
Method.
Background technology
Carbon content is the key technical index of hard alloy, largely determines the mechanical-physical of hard alloy
Can, the carbon in hard alloy is primarily present two kinds of forms：Refractory carbide is formed first, being combined with refractory metal；Second is that single
Matter free carbon, the saturation carbon content of refractory carbide can make to exist in hard alloy within the scope of one, higher than underrange
Free carbon can make metal carbides in hard alloy lack carbon, form decarburization η phases, decarburization η phases in hard alloy less than underrange
It is present between Binder Phase and hard phase, as impurity defect, its appearance can reduce the machinery of hard alloy for the generation of η phases
Physical property, thus to produce good hard metal article and must just eliminate decarburization defect.
Currently, the method for eliminating hard metal article decarburization defect predominantly is completed to take off in a vacuum furnace using filler mode
Carbon returns burning, and stuffing process has the following problems：1) filler mode can only be integrally embedded to, i.e., be whole, Bu Nengxuan to product package
Selecting property carrying out decarburization to decarburization position returns burning；2) filler mode often uses alundum (Al2O3) powder, in vacuum sintering furnace or
Decarburization is carried out under low-pressure sintering furnace and returns burning, is vacuumized in sintering process, alundum (Al2O3) powdered form can be because of powdered form weight
Amount is diffused to when gently vacuumizing inside burner hearth or even in vacuum pipe, and sintering furnace is caused to damage；3) filler mode is due to needing
It is poor to eliminate adaptability to the decarburization of Large scale alloy product for the specific box-packed load filler of boat and alloy product；4)
Filler mode needs to detach alloy product with decarburization filler with sieve after the completion of sintering, and process is longer, and cost is higher.
Invention content
Can burning selectively be returned to the progress decarburization of decarburization position the purpose of the present invention is to provide one kind and prevent three oxygen
Change the method for the elimination hard alloy decarburization defect of two aluminium powders damage sintering furnace.
This method for eliminating hard alloy decarburization defect provided by the invention, including：
Titanium dioxide, carbon black and solvent are configured to coating；
Then coating is uniformly applied to carbide surface, carries out decarburization and returns burning；
The hard alloy progress blasting treatment after burning is returned to decarburization to be eliminated de- to clean up the coating of alloy surface
The hard alloy of carbon defects.
With the total weight of titanium dioxide and carbon black, titanium dioxide in the coating, carbon black weight percent be respectively
20~35%, 65~80%, the additive amount of the solvent is the 15~25% of the total weight of titanium dioxide and carbon black.
The titanium dioxide selects titanium dioxide, purity >=99.0%.
The carbon black selects high-purity carbon black, purity >=99.0%.
The solvent is pure water or deionized water.
The coating is formulated by following manner：After titanium dioxide and carbon black are mixed, adds solvent and be uniformly mixed
After be made.
According to the difference of the decarburization phase rank of hard alloy, adjusts the percentage of titanium dioxide and carbon black in coating and contain
Amount.
For the hard alloy of following decarburization phase ranks, the weight percent of titanium dioxide and carbon black in coating is as follows：
Above-mentioned percentage is with the total weight of titanium dioxide and carbon black.
The decarburization is returned burning and is sintered using vacuum sintering furnace or pressure sintering furnace.
The heating cycle that burning is returned in the decarburization is：1350 DEG C are first warming up to, keeps the temperature 20~40min, then be warming up to 1450 DEG C,
30~50min is kept the temperature, then cools to room temperature with the furnace.
The principle of the present invention：Titanium dioxide main component is titanium dioxide, has a high stability, titanium dioxide itself and carbon,
Tungsten will not chemically react, but the effect of carbon potential balance can drive the free carbon in alloy medium high carbon area to be spread to low-carbon area,
Under certain temperature dissociate carbon spread and adsorb be deposited on titanium dioxide surface, while the carbon mixed in titanium dioxide at this temperature
Clandestine meeting occurs corresponding chemical reaction with decarburization η phases and forms the tungsten carbon compounds such as relatively stable tungsten carbide and ditungsten carbide, finally
Alloy product decarburization defect is eliminated, since η phases have higher chemical stability, cobalt phase therein is at 1440 DEG C or more, ability
It is fully converted into liquid phase, therefore burning temperature is returned into decarburization and is set to 1450 DEG C, may insure necessary η inversion of phases after keeping the temperature appropriate time
For tungsten carbide and ditungsten carbide.
Compared with prior art, advantageous effects of the invention：
This method for eliminating hard alloy decarburization defect provided by the invention, by coating (titanium dioxide-carbon black-solvent)
Covering decarburization position and qualified position is not smeared, can decarburization selectively be carried out to decarburization position and return burning；The present invention is by coating
It after smearing is covered in product surface, can be directly placed on the graphite boat of original carrying product, no special boat requirement, no
It needs to contain burning product to be returned using closed graphite, specific apparent advantage, hydrogen stuffing process carries out decarburization to product
Burning is returned, for the product size length of processing no more than 200mm, decarburization, which is returned, burns qualification rate no more than 80%, disappears using the present invention
Except the method for hard alloy decarburization defect, it can be returned with product of the treated length within 300mm, decarburization and burn qualification rate up to 95%.
This method for eliminating hard alloy decarburization defect provided by the invention, product surface is covered in by coating, can be with
It directly carries out returning burning using vacuum sintering furnace or low-pressure sintering furnace, paste coating is vacuumized in sintering process, will not be dissipated
Hair pollution sintering furnace and its pipeline so that sintering furnace continues normal sintered products, does not need any cleaning or uses special burning
Freezing of a furnace.
This method for eliminating hard alloy decarburization defect provided by the invention, by applying trowelling in carbide surface
Then material carries out decarburization and returns burning, blasting treatment, Metallographic Analysis result shows that the metallographic structure E classes of hard metal article are
E00 realizes the elimination of hard alloy decarburization defect, and process is short, and production cost is low.
Description of the drawings
Fig. 1 is the decarburization metallograph for the YG6X hard alloy that embodiment 1 is chosen.
Fig. 2 is using 1 method of embodiment treated YG6X hard alloy metallographs.
Fig. 3 is the decarburization metallograph for the YG6X hard alloy that embodiment 2 is chosen.
Fig. 4 is using 2 method of embodiment treated YG6X hard alloy metallographs.
Fig. 5 is the decarburization metallograph for the YG6X hard alloy that embodiment 3 is chosen.
Fig. 6 is using 3 method of embodiment treated YG6X hard alloy metallographs.
Specific implementation mode
The technical scheme in the embodiments of the invention will be clearly and completely described below, it is clear that described implementation
Example is only a part of the embodiment of the present invention, rather than whole embodiments, based on the embodiments of the present invention, the common skill in this field
The every other embodiment that art personnel are obtained without making creative work belongs to the model that the present invention protects
It encloses, present invention will be further explained below with reference to the attached drawings and specific examples.
Embodiment 1
The selection trade mark is YG6X, and model MAP019162-2.6, metallographic structure E classes are the hard metal article 23 of E50
Part, hard alloy metallograph are shown in Fig. 1.
Steps are as follows for specific method：Configuration 80% carbon black 0.80kg, remaining be 20% titanium dioxide 0.2kg, by carbon black with
After titanium dioxide stirs evenly, the total coating 1kg of carbon black-titanium dioxide is obtained, then it is the pure of carbon black-titanium dioxide total weight 25% to add weight
Water purification 0.25kg obtains coating after stirring evenly；Prepared coating is uniformly applied to the hard alloy of decarburization defect
Product surface is then placed in graphite boat；The graphite boat of hard alloy equipped with decarburization defect is put into vacuum sintering furnace,
1350 DEG C are first warming up to, 3min is kept the temperature, then heats to 1450 DEG C, soaking time 40min cools to room temperature with the furnace；Sintering
After the completion, product progress blasting treatment is burnt to returning, to clean up the coating of alloy surface, the hard for the decarburization defect that is eliminated closes
Gold.
The burned product that returns after blasting treatment is randomly selected by 3 therein does Metallographic Analysis, analysis result is 3 products
Metallographic structure C classes are C00, and specific metallograph is shown in Fig. 2.
Embodiment 2
The selection trade mark is YG6X, and model MAP019162-2.6, metallographic structure E classes are the hard metal article 22 of E06
Part, hard alloy metallograph are shown in Fig. 3.
Steps are as follows for specific method：Configuration 75% carbon black 0.75kg, remaining be 25% titanium dioxide 0.25kg, by carbon black with
After titanium dioxide stirs evenly, the total coating 1kg of carbon black-titanium dioxide is obtained, then it is the pure of carbon black-titanium dioxide total weight 20% to add weight
Water purification 0.20kg obtains coating after stirring evenly；Prepared coating is uniformly applied to the hard alloy of decarburization defect
Product surface is then placed in graphite boat；The graphite boat of hard alloy equipped with decarburization defect is put into vacuum sintering furnace,
1350 DEG C are first warming up to, 3min is kept the temperature, then heats to 1450 DEG C, soaking time 40min cools to room temperature with the furnace；Sintering
After the completion, product progress blasting treatment is burnt to returning, to clean up the coating of alloy surface, the hard for the decarburization defect that is eliminated closes
Gold.
The burned product that returns after blasting treatment is randomly selected by 3 therein does Metallographic Analysis, analysis result is 3 products
Metallographic structure E classes are E00, and specific metallograph is shown in Fig. 4.
Embodiment 3
The selection trade mark is YG6, and model MAP019162-2.6, metallographic structure E classes are the hard metal article 20 of E02,
Hard alloy metallograph is shown in Fig. 5.
Steps are as follows for specific method：Configuration 68% carbon black 0.68kg, remaining be 32% titanium dioxide 0.32kg, by carbon black with
After titanium dioxide stirs evenly, the total coating 1kg of carbon black-titanium dioxide is obtained, then it is the pure of carbon black-titanium dioxide total weight 15% to add weight
Water purification 0.15kg obtains coating after stirring evenly；Prepared coating is uniformly applied to the hard alloy of decarburization defect
Product surface is then placed in graphite boat；The graphite boat of hard alloy equipped with decarburization defect is put into vacuum sintering furnace,
1350 DEG C are first warming up to, 3min is kept the temperature, then heats to 1450 DEG C, soaking time 40min cools to room temperature with the furnace；Sintering
After the completion, product progress blasting treatment is burnt to returning, to clean up the coating of alloy surface, the hard for the decarburization defect that is eliminated closes
Gold.
The burned product that returns after blasting treatment is randomly selected by 3 therein does Metallographic Analysis, analysis result is 3 products
Metallographic structure E classes are E00, and specific metallograph is shown in Fig. 6.
The above is only a preferred embodiment of the present invention, protection scope of the present invention is not limited merely to above-mentioned implementation
Example.To those of ordinary skill in the art, obtained improvement and change in the case where not departing from the technology of the present invention concept thereof
It changes and also should be regarded as protection scope of the present invention.
Claims (10)
1. a kind of method for eliminating hard alloy decarburization defect, it is characterised in that including：
Titanium dioxide, carbon black and solvent are configured to coating；
Then coating is uniformly applied to carbide surface, carries out decarburization and returns burning；
Hard alloy after burning is returned to decarburization and carries out blasting treatment, the hard alloy for the decarburization defect that is eliminated.
2. requiring 1 method for eliminating hard alloy decarburization defect according to power, which is characterized in that titanium dioxide in the coating
Titanium, carbon black weight percent be respectively 20~35%, 65~80%, the additive amount of the solvent is titanium dioxide and carbon black
The 15~25% of total weight.
3. requiring 1 or 2 methods for eliminating hard alloy decarburization defect according to power, which is characterized in that the titanium dioxide choosing
With titanium dioxide, purity >=99.0%.
4. requiring 1 or 2 methods for eliminating hard alloy decarburization defect according to power, which is characterized in that the carbon black is selected high
Pure carbon black, purity >=99.0%.
5. requiring 1 or 2 methods for eliminating hard alloy decarburization defect according to power, which is characterized in that the solvent is pure
Water or deionized water.
6. requiring 1 or 2 methods for eliminating hard alloy decarburization defect according to power, which is characterized in that the coating is by following
Mode is formulated：After titanium dioxide and carbon black are mixed, adds solvent and be made after mixing.
7. requiring 1 or 2 methods for eliminating hard alloy decarburization defect according to power, which is characterized in that according to hard alloy
The difference of decarburization phase rank adjusts the percentage contents of titanium dioxide and carbon black in coating.
8. requiring 7 methods for eliminating hard alloy decarburization defect according to power, which is characterized in that for following decarburization phase ranks
Hard alloy, the weight percent of titanium dioxide and carbon black in coating is as follows：
Above-mentioned percentage is with the total weight of titanium dioxide and carbon black.
9. requiring 1 method for eliminating hard alloy decarburization defect according to power, which is characterized in that the decarburization returns burning using true
Empty sintering furnace or pressure sintering furnace sintering.
10. requiring 1 or 9 methods for eliminating hard alloy decarburization defect according to power, which is characterized in that burning is returned in the decarburization
Heating cycle is：1350 DEG C are first warming up to, keeps the temperature 20~40min, then be warming up to 1450 DEG C, 30~50min is kept the temperature, then with stove
It is cooled to room temperature.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109576637A (en) * | 2018-12-20 | 2019-04-05 | 株洲硬质合金集团有限公司 | A kind of method for carburizing of hard alloy |
| CN115029659A (en) * | 2022-05-06 | 2022-09-09 | 广东翔鹭钨业股份有限公司 | Method for eliminating hard alloy decarburization defect |
| CN115815597A (en) * | 2022-10-31 | 2023-03-21 | 成都美奢锐新材料有限公司 | Hard alloy burning-back device and hard alloy burning-back method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109576637A (en) * | 2018-12-20 | 2019-04-05 | 株洲硬质合金集团有限公司 | A kind of method for carburizing of hard alloy |
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| CN115815597A (en) * | 2022-10-31 | 2023-03-21 | 成都美奢锐新材料有限公司 | Hard alloy burning-back device and hard alloy burning-back method |
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