CN114058809A - Heat treatment method for forging die - Google Patents
Heat treatment method for forging die Download PDFInfo
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- CN114058809A CN114058809A CN202111365503.5A CN202111365503A CN114058809A CN 114058809 A CN114058809 A CN 114058809A CN 202111365503 A CN202111365503 A CN 202111365503A CN 114058809 A CN114058809 A CN 114058809A
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- die
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- tempering
- heat treatment
- temperature
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- 238000010438 heat treatment Methods 0.000 title claims abstract description 57
- 238000000034 method Methods 0.000 title claims abstract description 42
- 238000005242 forging Methods 0.000 title claims abstract description 19
- 238000005496 tempering Methods 0.000 claims abstract description 43
- 238000005121 nitriding Methods 0.000 claims abstract description 19
- 238000010791 quenching Methods 0.000 claims abstract description 18
- 230000000171 quenching effect Effects 0.000 claims abstract description 18
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 7
- 239000010959 steel Substances 0.000 claims abstract description 7
- 230000002035 prolonged effect Effects 0.000 claims abstract description 6
- 206010016256 fatigue Diseases 0.000 claims abstract description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 30
- 238000001816 cooling Methods 0.000 claims description 15
- 229910052757 nitrogen Inorganic materials 0.000 claims description 15
- 239000000463 material Substances 0.000 claims description 11
- 229910001566 austenite Inorganic materials 0.000 claims description 2
- 238000004321 preservation Methods 0.000 claims description 2
- 230000000630 rising effect Effects 0.000 claims description 2
- 238000005516 engineering process Methods 0.000 description 3
- 238000003754 machining Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000000137 annealing Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
Images
Classifications
-
- 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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
-
- 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
- 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
- C23C8/28—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 more than one element being applied in one step
- C23C8/30—Carbo-nitriding
- C23C8/32—Carbo-nitriding of ferrous surfaces
Abstract
The invention discloses a heat treatment method of a forge piece die, aiming at H13 die steel, on the basis of vacuum quenching and tempering, the surface nitriding treatment of the die is added; the invention has the advantages that: the die has higher integral comprehensive strength, the surface hardness and the wear resistance of the die are further improved, and the early fatigue generated in the die forging process is prevented by performing anti-seepage treatment on positions such as a die ejector rod hole and the like which are easy to generate fatigue cracks, so that the service life of the die is prolonged, and the die has better application prospect.
Description
Technical Field
The invention relates to the field of machining, in particular to a method for quenching and tempering and surface heat treatment of a forging die in the field of hot working.
Background
The heat treatment of the die is one of the key processes in the die manufacturing, is directly related to the manufacturing precision, mechanical properties (such as strength and the like), service life and manufacturing cost of the die, and is an important link for ensuring the quality and service life of the die. The reasonable heat treatment process is correctly selected, and the method plays an important role in fully playing the potential performance of the material, reducing energy consumption, reducing cost, improving the quality of the die and prolonging the service life of the die.
The conventional heat treatment of die steel mainly includes annealing, normalizing, quenching and tempering. The current fields of rapid development of the heat treatment technology of the die are a vacuum heat treatment technology and a surface nitriding technology of the die, but the two methods have certain limitations, and the vacuum heat treatment die has small deformation, no oxidation on the surface, high integral comprehensive strength, but slightly low surface hardness and slightly poor wear resistance; the surface of the mold subjected to surface nitriding treatment has high hardness and wear resistance of a nitrided layer on the surface of the mold, but the overall comprehensive strength of the mold is low. Therefore, a new method for solving the respective drawbacks is urgently needed.
Disclosure of Invention
In order to solve the technical problems, the invention aims to provide a novel die heat treatment process method, so that the service life of the die is further prolonged, the method is applied to the integral heat treatment and the surface heat treatment of a forge piece die, and after the heat treatment method is applied, the service life of the H13 die can be greatly prolonged. The specific method comprises the following steps:
a forge piece die heat treatment method is characterized in that for H13 die steel, on the basis of vacuum hardening and tempering, die surface nitriding treatment is added;
the vacuum quenching and tempering treatment refers to that the H13 material die is respectively treated by vacuum quenching and vacuum tempering processes; the vacuum quenching is as follows: heating the H13 material mould from normal temperature to 650-655 ℃ along with the furnace for 30 minutes, preserving heat for 240 minutes, then heating to 850-855 ℃ within 30 minutes, preserving heat for 180 minutes, then heating to 1030-1035 ℃ within 20 minutes, and then quenching in cooling oil at 60-80 ℃;
the vacuum tempering comprises three times of tempering, wherein the first tempering is that the temperature is preserved in a furnace at 580-640 ℃ for 360 minutes, and then nitrogen is used for cooling; the secondary tempering is that the temperature is preserved for 360 minutes in a furnace at 580-620 ℃, and then nitrogen is used for cooling; the third tempering is that the furnace is kept at 560-600 ℃ for 360 minutes and then is cooled by nitrogen;
the surface nitriding treatment process comprises the following steps: keeping the temperature in a furnace at 245-255 ℃ for 59-61 minutes, then heating to 395-405 ℃ and keeping the temperature for 59-61 minutes, and finally heating to 555-565 ℃ and nitrocarburizing for 355-365 minutes.
The heat treatment method of the forging die is combined heat treatment, the die has higher overall comprehensive strength through vacuum heat treatment, the surface of the die has higher hardness and better wear resistance through surface nitriding treatment, and early fatigue generated in the die forging process is prevented by performing anti-seepage treatment on positions such as a die ejector rod hole and the like which are easy to generate fatigue cracks, so that the service life of the die is prolonged.
When the die is quenched and heated, the temperature is gradually raised in three stages in the vacuum furnace, the integral temperature uniformity of the die is ensured, and the integral toughness and tempering resistance of the quenched die are improved.
After the die is quenched, the residual austenite in the steel is reduced through three times of tempering, so that the structure of the die after tempering is uniform, the final strength and toughness of the die are improved, and the die has higher comprehensive strength.
When the mould nitrogenize, carry out progressively heating and rising temperature in nitriding furnace in three stages, guarantee the homogeneity of mould bulk temperature, the heat preservation process of second stage before nitrocarburizing is the preoxidation treatment to the mould simultaneously, can improve the efficiency that final third stage nitrocarburizing, practices thrift the nitriding time.
The invention has the advantages that:
by the combined heat treatment method of vacuum heat treatment and surface nitriding, the forging die has high overall comprehensive strength, high surface hardness and high wear resistance, so that the service life of the die is greatly prolonged, the cost of the forging is reduced, and the forging die has a good application prospect.
Drawings
FIG. 1 is a graph of a vacuum quenching process;
FIG. 2 is a graph of a vacuum tempering process;
FIG. 3 is a graph of a nitridation heat treatment process.
Detailed Description
For a forging die made of a certain H13 die steel material and needing vacuum heat treatment, before the die is formed, the vacuum heat treatment is adopted to carry out die integral treatment, so that the die has higher integral hardness. Then, processing the surface of the cavity of the die, and performing surface nitriding treatment on the processed die to ensure that the die has higher surface hardness and wear resistance, wherein the process flow and the parameters are as follows:
1. the process flow comprises the following steps:
module blanking, rough machining, vacuum tempering, finish machining and forming, surface nitriding and surface polishing
2. The technological parameters are as follows:
example 1
Vacuum quenching: heating the H13 material die to 650 ℃ from normal temperature along with the furnace for 30 minutes, preserving heat for 240 minutes, then heating to 855 ℃ within 30 minutes, preserving heat for 180 minutes, then heating to 1035 ℃ within 20 minutes, and then quenching in cooling oil at 70 ℃;
vacuum tempering: the method comprises three times of tempering, wherein the first tempering is that the temperature is preserved in a 580 ℃ furnace for 360 minutes, and then nitrogen is used for cooling; the secondary tempering is that the temperature is preserved for 360 minutes in a furnace at 600 ℃, and then nitrogen is used for cooling; the third tempering is that the furnace is kept at the temperature of 600 ℃ for 360 minutes and then is cooled by nitrogen;
surface nitriding: the temperature is maintained in a furnace at 250 ℃ for 59 minutes, then heated to 400 ℃ for 60 minutes, and finally heated to 555 ℃ for nitrocarburizing for 355 minutes.
Example 2
Vacuum quenching: heating the H13 material die to 653 ℃ along with the furnace for 30 minutes at normal temperature, preserving heat for 240 minutes, then heating to 852 ℃ within 30 minutes, preserving heat for 180 minutes, then heating to 1032 ℃ within 20 minutes, and then quenching in cooling oil at 60 ℃;
vacuum tempering: the method comprises three times of tempering, wherein the first tempering is that the temperature is kept in a furnace at 640 ℃ for 360 minutes, and then nitrogen is used for cooling; the secondary tempering is that the furnace is kept at the temperature of 620 ℃ for 360 minutes and then is cooled by nitrogen; the third tempering is that the temperature of the 580 ℃ furnace is preserved for 360 minutes, and then nitrogen is used for cooling;
surface nitriding: keeping the temperature in a 255 ℃ furnace for 61 minutes, then heating to 405 ℃ and keeping the temperature for 59-61 minutes, finally heating to 565 ℃ and nitrocarburizing for 365 minutes.
Example 3
Vacuum quenching: heating the H13 material die to 655 ℃ along with the furnace for 30 minutes from normal temperature, preserving heat for 240 minutes, then heating to 850 ℃ within 30 minutes, preserving heat for 180 minutes, then heating to 1030 ℃ within 20 minutes, and then quenching in cooling oil at 80 ℃;
vacuum tempering: the method comprises three times of tempering, wherein the first tempering is that the temperature is preserved in a furnace at 610 ℃ for 360 minutes, and then nitrogen is used for cooling; the secondary tempering is that the temperature is preserved for 360 minutes in a 580 ℃ furnace, and then nitrogen is used for cooling; the third tempering is that the furnace is kept at 560 ℃ for 360 minutes and then is cooled by nitrogen;
surface nitriding: maintaining at 245 deg.c for 60 min, heating to 395 deg.c for 59-61 min, and final heating to 560 deg.c for nitrocarburizing for 360 min.
The die processed according to the process has higher overall comprehensive strength and higher surface hardness and wear resistance than a common die, so that the die has longer service life than a die processed in a common processing mode, and the cost of the die and a forging piece is reduced.
The hardness of the H13 material die base, the surface hardness and the number of die forged parts after heat treatment according to the method of the present invention are given in Table 1:
TABLE 1
As can be seen from Table 1, the basic hardness of the die is improved, the surface hardness reaches about 680(HV), the number of die forging parts reaches more than 4000 (parts), and the die is obviously superior to a common tempering die made of the same material.
Claims (5)
1. A heat treatment method for a forging die is characterized by comprising the following steps: aiming at H13 die steel, on the basis of vacuum hardening and tempering, the surface nitriding treatment of the die is added;
the vacuum quenching and tempering treatment refers to that the H13 material die is respectively treated by vacuum quenching and vacuum tempering processes; the vacuum quenching is as follows: heating the H13 material mould from normal temperature to 650-655 ℃ along with the furnace for 30 minutes, preserving heat for 240 minutes, then heating to 850-855 ℃ within 30 minutes, preserving heat for 180 minutes, then heating to 1030-1035 ℃ within 20 minutes, and then quenching in cooling oil at 60-80 ℃;
the vacuum tempering comprises three times of tempering, wherein the first tempering is that the temperature is preserved in a furnace at 580-640 ℃ for 360 minutes, and then nitrogen is used for cooling; the secondary tempering is that the temperature is preserved for 360 minutes in a furnace at 580-620 ℃, and then nitrogen is used for cooling; the third tempering is that the furnace is kept at 560-600 ℃ for 360 minutes and then is cooled by nitrogen;
the surface nitriding treatment process comprises the following steps: keeping the temperature in a furnace at 245-255 ℃ for 59-61 minutes, then heating to 395-405 ℃ and keeping the temperature for 59-61 minutes, and finally heating to 555-565 ℃ and nitrocarburizing for 355-365 minutes.
2. The forging die heat treatment method of claim 1, wherein: the heat treatment method of the forging die is combined heat treatment, the die has higher overall comprehensive strength through vacuum heat treatment, the surface of the die has higher hardness and better wear resistance through surface nitriding treatment, and early fatigue generated in the die forging process is prevented by performing anti-seepage treatment on positions such as a die ejector rod hole and the like which are easy to generate fatigue cracks, so that the service life of the die is prolonged.
3. The forging die heat treatment method of claim 1, wherein: when the die is quenched and heated, the temperature is gradually raised in three stages in the vacuum furnace, the integral temperature uniformity of the die is ensured, and the integral toughness and tempering resistance of the quenched die are improved.
4. The forging die heat treatment method of claim 1, wherein: after the die is quenched, the residual austenite in the steel is reduced through three times of tempering, so that the structure of the die after tempering is uniform, the final strength and toughness of the die are improved, and the die has higher comprehensive strength.
5. The forging die heat treatment method of claim 1, wherein: when the mould nitrogenize, carry out progressively heating and rising temperature in nitriding furnace in three stages, guarantee the homogeneity of mould bulk temperature, the heat preservation process of second stage before nitrocarburizing is the preoxidation treatment to the mould simultaneously, can improve the efficiency that final third stage nitrocarburizing, practices thrift the nitriding time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111365503.5A CN114058809A (en) | 2021-11-18 | 2021-11-18 | Heat treatment method for forging die |
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| CN202111365503.5A CN114058809A (en) | 2021-11-18 | 2021-11-18 | Heat treatment method for forging die |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115058681A (en) * | 2022-06-28 | 2022-09-16 | 江苏华东三和兴模具材料有限公司 | Nitriding production process for prolonging service life of die-casting die |
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| CN110016638A (en) * | 2019-04-25 | 2019-07-16 | 兰州理工大学 | A kind of processing method of phosphorous copper balls extrusion die |
| CN111992655A (en) * | 2019-05-27 | 2020-11-27 | 辽宁五一八内燃机配件有限公司 | Die forging method for integral crankshaft of large internal combustion engine |
-
2021
- 2021-11-18 CN CN202111365503.5A patent/CN114058809A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR19980083176A (en) * | 1997-05-12 | 1998-12-05 | 정수진 | Manufacturing method of heat treatment of mold material |
| US20020112787A1 (en) * | 2000-12-14 | 2002-08-22 | Nissan Motor Co., Ltd. | High-strength race and method of producing the same |
| JP2006322042A (en) * | 2005-05-19 | 2006-11-30 | Nachi Fujikoshi Corp | Nitrided steel with superhigh hardness and high abrasion resistance |
| JP2010255095A (en) * | 2009-03-31 | 2010-11-11 | Jfe Steel Corp | Method for manufacturing bearing-component excellent in rolling fatigue characteristics under foreign matter environment |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115058681A (en) * | 2022-06-28 | 2022-09-16 | 江苏华东三和兴模具材料有限公司 | Nitriding production process for prolonging service life of die-casting die |
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