CN1004284B - Deformation annealing process for high-speed tool steel - Google Patents
Deformation annealing process for high-speed tool steel Download PDFInfo
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- CN1004284B CN1004284B CN87102389.XA CN87102389A CN1004284B CN 1004284 B CN1004284 B CN 1004284B CN 87102389 A CN87102389 A CN 87102389A CN 1004284 B CN1004284 B CN 1004284B
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- 238000000137 annealing Methods 0.000 title claims abstract description 71
- 238000000034 method Methods 0.000 title claims abstract description 20
- 229910001315 Tool steel Inorganic materials 0.000 title claims abstract description 10
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 64
- 239000010959 steel Substances 0.000 claims abstract description 64
- 230000009466 transformation Effects 0.000 claims abstract description 21
- 238000001816 cooling Methods 0.000 claims abstract description 20
- 229910000734 martensite Inorganic materials 0.000 claims abstract description 19
- 238000005516 engineering process Methods 0.000 claims description 22
- 238000009413 insulation Methods 0.000 claims description 16
- 238000002791 soaking Methods 0.000 claims description 9
- 239000000463 material Substances 0.000 claims description 6
- 239000002918 waste heat Substances 0.000 claims description 4
- 238000005265 energy consumption Methods 0.000 abstract description 4
- 230000007547 defect Effects 0.000 abstract 1
- 238000004321 preservation Methods 0.000 abstract 1
- 230000000930 thermomechanical effect Effects 0.000 description 14
- 238000005098 hot rolling Methods 0.000 description 8
- 238000004519 manufacturing process Methods 0.000 description 7
- 238000010791 quenching Methods 0.000 description 7
- 238000005097 cold rolling Methods 0.000 description 6
- 230000000171 quenching effect Effects 0.000 description 6
- 238000011084 recovery Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 238000007669 thermal treatment Methods 0.000 description 5
- 229910052799 carbon Inorganic materials 0.000 description 4
- 238000005496 tempering Methods 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 230000006911 nucleation Effects 0.000 description 3
- 238000010899 nucleation Methods 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 208000037656 Respiratory Sounds Diseases 0.000 description 2
- 238000005275 alloying Methods 0.000 description 2
- 229910001566 austenite Inorganic materials 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 238000005482 strain hardening Methods 0.000 description 2
- 229910000997 High-speed steel Inorganic materials 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000005261 decarburization Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000005242 forging Methods 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 238000010583 slow cooling Methods 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
- 230000003245 working effect Effects 0.000 description 1
Classifications
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- 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
- Y02P10/20—Recycling
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- Heat Treatment Of Steel (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The present invention relates to a new annealing process of high-speed tool steel after hot working deformation. The method is characterized in that the annealing treatment is carried out in two stages: the first stage is that after hot working, the steel is insulated at any temperature between the martensite transformation temperature Ms and 680 ℃ by utilizing deformation; the second stage is heat preservation at any temperature between 700 ℃ and A ↓ [ c 1 ]. It overcomes a series of defects caused by martensite phase transformation caused by cooling to room temperature after hot working in the traditional process. Not only can avoid the cracks of the steel after hot working to obtain proper hardness, but also can improve the structure and the performance of the steel, improve the quality and the yield of the steel and reduce the energy consumption.
Description
The invention belongs to Heat Treatment Of Steel technology.Mainly be applicable to steel ingot, intermediate blank, steel and the workpiece anneal after forging, hot rolling and other various forms of thermal processing distortions of rapid tool steel.
Usually, rapid tool steel all is that room temperature is arrived in slow cooling after various thermal processing distortions, carries out anneal then.The annealed purpose is: eliminate because hot-work and the various stress and the harmful structure that produce with postcooling, reduce hardness, improve plasticity, improve the distribution and the form of carbide in the steel, be next step processing treatment preparatory condition, as providing hardness and the suitable blank of plasticity for cold machining and cold-drawn, cold rolling processing etc.; Carrying out tissue for next step thermal treatment prepares.
In order to achieve the above object, the general following traditional thermal treatment process ((SG examines general work " high speed Heat Treatment Of Steel " metallurgical industry press, P120～125), (" thermal treatment " 1973, VoL13, No1, P61 Japanese)) that adopts in the prior art
(1) for higher rapid steel of carbon and alloying element content and die steel etc., owing to produced martensitic transformation in the process of cooling thermal processing distortion after, when annealing, need be heated to transformation temperature (A with base or material from room temperature
Cl) more than carry out high temperature annealing.Generally in soak about 5 hours, controlled temperature slowly cooled off then, and speed of cooling is about 15～20 ℃/hour, and therefore, annealing time is very long.
(2) for the higher martensite steel sections of hardening capacity, generally be to adopt the high tempering mode to anneal, promptly be warming up to up to 700 ℃ to A from room temperature
ClCertain temperature insulation annealing between the point.Sometimes need repeatedly several times, annealing hardness just can lower.
There is following shortcoming in this traditional thermal treatment process:
(1) the hot-work postcooling has produced martensitic transformation to room temperature in steel, causes easily cracking in the steel, causes waste product.So necessary controlled chilling condition makes speed of cooling unlikely too fast, normally adopt and cheat cold or cooling in heap etc.Even if but like this, speed of cooling still is difficult to control, if improper, still can crack, sometimes, the crackle rate is very high.In addition,, also can influence other character of steel, as plasticity etc. owing to produced martensitic transformation in the steel.
(2), must carry out transformation temperature (A for rapid steel
Cl) above high temperature annealing, annealing temperature sometimes up to 870～880 ℃, and needs long-time slowly cooling about 850 ℃, and the production cycle reaches more than 60 hours sometimes.Like this, the one, the cycle is long, and production efficiency is low, the energy consumption height; The 2nd, the annealing temperature height makes the carbide chap, influences the tissue and the performance of steel, influences the work-ing life of steel; Simultaneously, also make the decarburization of steel and oxidative phenomena serious.
(3) for hardening capacity very high steel or A
ClLower steel though be at the following annealing temperature of transformation temperature, needs usually to handle that annealing hardness is lowered, the production cycle lengthening, even like this, annealing hardness is still higher sometimes, fails to reach requirement.
(4) steel billet after the hot-work, steel or workpiece are deposited in on-the-spot cooling, and the one, waste heat dissipates in vain, causes waste; The 2nd, envrionment temperature is risen, labor condition is relatively poor.
In a word, the distinct disadvantage of this traditional technology is that thermal processing distortion and anneal subsequently disconnect, and has produced martensitic transformation in steel, has brought a series of problem thus, has caused waste and trouble, and makes some degradation of steel.
For some rapid steel workpiece, also have after hot-work, directly carry out about 750 ℃ that isothermal annealing handles.Though this processing can make annealing hardness reach requirement, discovery proeutectoid carbide in irregular shape is separated out along austenite grain boundary in the steel, and comparatively small amt, and skewness have influenced the quality of steel, and also is difficult to realize in actual production.
The objective of the invention is to overcome above-mentioned shortcoming, the annealing technology behind a kind of Rapid Steel Tool steel thermal processing distortion is provided.Thermal processing distortion closely is connected with subsequently anneal, makes after hot-work, not produce martensitic transformation in the steel substantially.Like this, can avoid steel billet, steel or workpiece after hot-work, to crack, obtain suitable annealing hardness, can improve the tissue and the performance of processed steel again, make the proeutectoid carbide of separating out in the steel, not only small and dispersed, quantity is many, and be evenly distributed, can improve the tempered-hardness of quenching of steel, improve plasticity; When the step operation requires under satisfying fully, can also reach save energy, reduce equipment loss, shorten production cycle and the purpose that significantly improves economic benefit.
Concrete thermomechanical annealing process program of the present invention divides two stages, i.e. fs (low-temperature zone) and subordinate phase (high temperature section).Existing division is as follows:
(1) fs (low-temperature zone): after hot-work, the steel material is placed stove, utilize waste heat, under the arbitrary temperature between Ms to 680 ℃ of this steel martensitic phase height temperature, be incubated 0.5～10 hour.
(2) subordinate phase (high temperature section): be right after the fs, the holding temperature that the steel material was undertaken by the fs is raised to 700 to A
ClPut the arbitrary temperature between the temperature, and be incubated 2-10 hour, subsequently cold the or air cooling of stove.
The effect of thermomechanical annealing technology fs and temperature range thereof are selected according to as follows: steel is cooled to ℃ insulation of the above temperature to 680 of martensitic phase height after hot-work, do not produce (or few generation) martensitic transformation, make the proeutectoid carbide homogeneous nucleation, this is the effect in the low-temperature zone insulation.Its ceiling temperature should guarantee carbide energy homogeneous nucleation, so that can there be the proeutectoid carbide of more small and dispersed to separate out in the steel, and is evenly distributed; Its lower limit temperature generally should be on the martensitic phase height.But hot processing temperature is not high sometimes, soaking time is not long, and the not high person of carbon and alloying element content in the matrix, both just holding temperature was lower than the martensitic phase height slightly, a small amount of martensitic transformation is arranged, annealing hardness and tissue influence to steel are also little, still can meet the demands, but generally be not less than the martensitic phase height.
The effect of thermomechanical annealing technology subordinate phase and temperature thereof are selected foundation: be incubated in high temperature section, finish perlitic transformation, the defective that elimination produces in hot procedure makes proeutectoid carbide further separate out, grow up, and makes it being evenly distributed on the matrix of disperse.Like this, the annealing hardness of steel is lower, can satisfy the requirement of step operation (as cold working process) down; Simultaneously, because annealing temperature is lower, primary carbide is difficult to grow up, and proeutectoid carbide quantity is more, make steel quenching and tempering afterwards after, obtain higher hardness, guarantee that steel has favorable tissue and performance.This is the effect in the high temperature section insulation.Its lower limit temperature should be able to guarantee that the annealing hardness of steel is lower, generally can be controlled in 700 ℃ or higher slightly; Its ceiling temperature should be lower than A
ClThe point.Because in the low-temperature zone insulation, proeutectoid carbide can homogeneous nucleation earlier.The adverse consequences of both having avoided martensitic transformation to bring has avoided erose carbide to separate out along austenite grain boundary again, makes steel that plasticity preferably be arranged.
The present invention is a kind of special thermomechanical treatment technology.At present, mostly thermomechanical treatment both at home and abroad is to be used for technologies such as deformation quenching, deformation normalizing, and purpose is to improve intensity, improves plasticity and toughness etc., but the deformation annealing process is not arranged as yet.After thermal processing distortion, in steel, produce a large amount of dislocations, can impel carbide to separate out and quicken Elements Diffusion.The present invention has utilized deformation induced carbide to separate out the principle of quickening phase transformation with deformation just, annealing is right after after hot-work, in specific temperature range, carry out, not only can reduce annealing temperature and shorten annealing time, and can obtain better tissues and performance.For the rapid tool steel of high-carbon high-alloy, after subordinate phase insulation, carbide evenly, separate out to disperse, pearlitic transformation is finished, therefore, speed of cooling subsequently can be very fast, and is can stove cold, even air cooling, performance can meet the demands fully.Yet traditional annealing process must carry out high temperature annealing, after being incubated about 850 ℃, steel is austenitic state, and it is to carry out in process of cooling subsequently that carbide is separated out with perlitic transformation, so speed of cooling must be very slow, transformation is carried out more fully, obtained thinner tissue and lower hardness, otherwise, do not reach requirement, common speed of cooling is 15～20 ℃/hour, is cooled to 650 ℃ from 850 ℃, needs more than 10 hours, therefore, annealing time is very long.
The also visible accompanying drawing 1 of the concrete scheme of thermomechanical annealing technology.
Description of drawings
Accompanying drawing 1 is the thermomechanical annealing technology Parameter Map.
Accompanying drawing 2 is W
9Mo
3Cr
4The metallographic structure stereoscan photograph (multiple 1250 *) of V steel after the present invention handles.
Accompanying drawing 3 is W
9Mo
3Cr
4The metallographic structure stereoscan photograph (multiple 1250 *) of V steel after traditional annealing process is handled.
In the accompanying drawing 1, abscissa be time τ (hour), ordinate be temperature t (℃), dotted line 1 is martensitic transformation temperature Ms, dotted line 2 is A
ClTemperature, dotted line 3 is 680 ℃ of the ceiling temperatures of fs (cold zone) insulation, dotted line 4 is 700 ℃ of the lower limit temperatures of subordinate phase (high-temperature zone) insulation, and 5 is the soaking time (0.5～10 hour) of fs, and 6 is the soaking time (2～10 hours) of subordinate phase.
Adopt thermomechanical annealing technology of the present invention can obtain excellent effect: the first, annealing hardness is lower, as high speed steel W
9Mo
3Cr
4V and M
2Annealing hardness all at HB
240Below; The second, secondary fine carbide quantity is many in the steel, and disperse and being evenly distributed.Comparative drawings figs 2 and accompanying drawing 3 just can find out that in the metallographic structure after traditional annealing process is handled, its proeutectoid carbide quantity obviously is less than the present invention; The 3rd, quench after the annealing and tempering, can obtain higher hardness, all can reach more than the HRO67, improve about 1HRC than traditional technology; The 4th, the plasticity of steel improves, and is easy to proceed cold working etc., and the product lumber recovery is improved.
Compare with traditional existing annealing process, thermomechanical annealing technology of the present invention has following superiority:
(1) anneal is right after after the hot-work heating and carries out, and makes rapid tool steel not produce martensitic transformation after hot-work, has avoided the crackle generation, has reduced waste product; Improved the annealed structure and the performance of steel simultaneously, improved the quality of steel, the quenching of rapid tool steel, tempered-hardness are improved, and plasticity improves, be easy to proceed cold-drawn, cold deformation such as cold rolling, improve lumber recovery.
(2) annealing temperature reduces, and annealing time shortens, and utilizes waste heat, therefore, has reduced energy consumption, obvious economic.
(3) shorten the production cycle, reduced devices consume, improved plant factor.In the existing annealing process, the annealing temperature height, the gentle cool time of insulation is long, makes the production cycle long, and the effective rate of utilization of equipment is little, and energy consumption and devices consume are all bigger.
Embodiment one
Adopt thermomechanical annealing technology of the present invention to W
9Mo
3Cr
4V, W
6Mo
5Cr
4V
2Carry out anneal after the hot-work Deng 5 kinds of hot rolling materials of grade of steel.The hot-rolled temperature of test grade of steel and hot rolling material is listed table 1 in.Behind the above-mentioned steel hot rolling, carry out the low-temperature zone anneal of fs, concrete annealing temperature and time are as shown in table 1.After the fs insulation, and on existing annealing furnace, continue to heat up the processing of beginning subordinate phase.When temperature is raised to the temperature of subordinate phase setting, be incubated, secondary stage annealing temperature and soaking time are listed table 1 in.After the subordinate phase insulation, carry out the cold or air cooling of stove respectively.Annealing hardness of steel (HB) and the tempered-hardness of quenching (HFC) are as shown in table 2 behind thermomechanical annealing.
Embodiment two
Present embodiment is the simultaneous test of the hot rolling slab that cooling rolls usefulness being carried out traditional annealing process and annealing technology of the present invention after hot-work.The purpose of this annealing process is to improve cold rolling slab cold plasticity,, raising lumber recovery cold rolling to be convenient to.The test steel grade is the W of same stove
9Mo
3Cr
4The V rapid steel.
The tradition annealing process is as follows: will be at the W after 870 ℃ of temperature hot rollings
9Mo
3Cr
4V steel billet stockpile is as cold as room temperature, then blank is put into heat treatment furnace, is warmed up to 850 ℃ from room temperature, and the heating-up time is more than 15 hours, and soaking time is 5 hours; Insulation back is cooled to 550 ℃ with 15～20 ℃/hour speed from 850 ℃, and then air cooling, and cooled off after, need carry out a cold-forming pre-treatment more than 20 hours cooling time again, so that further reduce yield strength, increases cold plasticity.For this reason, continue blank is put into normalizing furnace, and be warmed up to 730～750 ℃, be incubated 0.5～2 hour.After the insulation, it is air-cooled to 330 ℃ to come out of the stove one by one, air cooling then, and coming out of the stove to whole heap blank finishes, and needs consuming time more than 10 hours.
The whole anneal time of above-mentioned traditional annealing process needs more than 60 hours.
The blank that annealing is finished carries out cold rolling, and its lumber recovery is 50%.
Annealing technology of the present invention is as follows: will be under 870 ℃ of temperature the blank after the hot rolling be right after hot rolling and be placed in the heat treatment furnace, carry out first stage annealing 450 ℃ of temperature, soaking time 1 hour; After the insulation, and then continue to heat up, carry out the anneal of subordinate phase, annealing temperature is 870 ℃, and soaking time is 5 hours, and after insulation finished, it is cold that whole heap blank carries out stove, whole anneal 20 hours consuming time altogether.Blank after the annealing carries out cold rolling, and its lumber recovery reaches 60.1%.
Find out that by this embodiment compare with traditional annealing process, the time that annealing technology of the present invention consumed shortens greatly, can shorten at least more than 20 hours; And saved thermal treatment process before the cold-forming; Lumber recovery improves 10%, remarkable in economical benefits.
The concrete processing parameter of table 1 embodiment thermomechanical annealing technology
Behind the table 2 embodiment thermomechanical annealing and the hardness after the tempering of quenching again
Claims (3)
1, the annealing technology behind a kind of rapid tool steel thermal processing distortion, it is characterized in that carrying out after this annealing technology is connected on hot-work, and novel process divides two stages to carry out: the fs is after hot-work, utilize waste heat, arbitrary temperature between Ms to 680 ℃ of this steel martensitic transformation temperature is incubated, subordinate phase is after being right after the fs insulation, to continue to be warmed up to 700 ℃ of A to this steel by the fs holding temperature
ClArbitrary temperature between the temperature is incubated.
2, annealing technology according to claim 1, the soaking time that it is characterized in that the fs is 0.5～10 hour, the soaking time of subordinate phase is 2～10 hours.
3, annealing technology according to claim 1, when it is characterized in that subordinate phase finishes, the steel material is the cold or air cooling of stove subsequently.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN87102389.XA CN1004284B (en) | 1987-04-01 | 1987-04-01 | Deformation annealing process for high-speed tool steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN87102389.XA CN1004284B (en) | 1987-04-01 | 1987-04-01 | Deformation annealing process for high-speed tool steel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1030097A CN1030097A (en) | 1989-01-04 |
| CN1004284B true CN1004284B (en) | 1989-05-24 |
Family
ID=4813938
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN87102389.XA Expired CN1004284B (en) | 1987-04-01 | 1987-04-01 | Deformation annealing process for high-speed tool steel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1004284B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1042240C (en) * | 1995-07-21 | 1999-02-24 | 宝山钢铁(集团)公司 | High-temp. high-alloy billet annealing method |
| WO2007119721A1 (en) * | 2006-04-11 | 2007-10-25 | Hitachi Metals, Ltd. | Method of pretreatment for quenching of martensitic tool steel and method of quenching |
| WO2008081517A1 (en) * | 2006-12-27 | 2008-07-10 | Hitachi Metals, Ltd. | Method for manufacturing tool steel |
| CN102851464A (en) * | 2012-09-22 | 2013-01-02 | 山东泰山钢铁集团有限公司 | Annealing technique of SUS410S martensitic stainless steel hot-rolled plate |
| CN107245565A (en) * | 2017-06-13 | 2017-10-13 | 中原特钢股份有限公司 | The stress relief annealing method of the effective steel continuous casting round bloom of high-pressure boiler |
| CN110257601A (en) * | 2019-07-12 | 2019-09-20 | 河冶科技股份有限公司 | The secondary ultra-soft spheroidizing method of high speed steel |
-
1987
- 1987-04-01 CN CN87102389.XA patent/CN1004284B/en not_active Expired
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| Publication number | Publication date |
|---|---|
| CN1030097A (en) | 1989-01-04 |
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