CN110938733A - Production process for quenching and tempering high-strength stainless steel fastener - Google Patents
Production process for quenching and tempering high-strength stainless steel fastener Download PDFInfo
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- CN110938733A CN110938733A CN201911401718.0A CN201911401718A CN110938733A CN 110938733 A CN110938733 A CN 110938733A CN 201911401718 A CN201911401718 A CN 201911401718A CN 110938733 A CN110938733 A CN 110938733A
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- 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
- C21D1/25—Hardening, combined with annealing between 300 degrees Celsius and 600 degrees Celsius, i.e. heat refining ("Vergüten")
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- 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
- C21D1/26—Methods of annealing
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- 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
- C21D1/56—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering characterised by the quenching agents
- C21D1/58—Oils
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- 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
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- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention discloses a production process for quenching and tempering a high-strength stainless steel fastener, which comprises the following process steps: putting the product into an annealing furnace for annealing treatment, cooling the product along with the furnace to 350-400 ℃, and taking out for air cooling; quenching, namely putting the pretreated workpiece into a high-temperature furnace, heating to 840-860 ℃, preserving heat for 0.5-1h, heating to 1080-1100 ℃ and preserving heat for 2-3h, quickly discharging after heat preservation, cooling in an oil cooling mode in a quenching tank, cooling the oil to 150-200 ℃, and taking out for air cooling; tempering, namely putting the quenched workpiece into a high-temperature furnace, heating to the temperature of 320-; and (3) putting the workpiece into an alkaline solution for descaling for 10-20min, and finally cleaning, drying and packaging the workpiece. An annealing pretreatment process is added before tempering, so that the original structure refined grain size of the stainless steel heat-resistant steel forging can be improved, and the tempering effect is improved.
Description
Technical Field
The invention relates to the technical field of quenching and tempering, in particular to a production process for quenching and tempering a high-strength stainless steel fastener.
Background
With the rapid development of science and technology in China, the level of equipment manufacturing industry is continuously improved, industries such as petroleum and petrochemical industry, aerospace and shipbuilding are in cluster development, in order to meet the requirements of light weight and corrosion resistance, the stainless steel fastener is used for replacing alloy steel and carbon steel fasteners in the development direction at present and in the future, the stainless steel fastener is generally subjected to thermal refining treatment to improve the mechanical properties such as strength, plasticity and toughness of the stainless steel fastener, the current thermal refining treatment process is simple one-time quenching and one-time tempering, products prepared by the simple thermal refining treatment mode are insufficient in hardness and strength, the rejection rate is high, and therefore a production process for thermal refining treatment of high-strength stainless steel fasteners is provided for solving the problems.
Disclosure of Invention
The invention aims to provide a production process for quenching and tempering a high-strength stainless steel fastener, so as to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme: a production process for quenching and tempering high-strength stainless steel fasteners is characterized in that an annealing pretreatment process is added before quenching and tempering, the refined grain size of the original structure of the stainless steel fasteners is improved, and the quenching and tempering treatment is carried out, and comprises the following process steps:
s1 annealing pretreatment
Putting the product into an annealing furnace for annealing treatment, wherein the annealing treatment temperature is 740-760 ℃, the annealing time is 2.5-3.5h, then cooling the product to 350-400 ℃ along with the furnace, taking the product out, and putting the product into air for cooling for 2-3 h;
s2 quenching
Placing the pretreated workpiece into a high-temperature furnace, heating to 840-860 ℃, preserving heat for 0.5-1h, heating to 1080-1100 ℃ and preserving heat for 2-3h, after the heat preservation is finished, rapidly discharging, cooling in a quenching tank by adopting an oil cooling mode, cooling the oil to 150-200 ℃, and taking out for air cooling;
s3 tempering
Putting the quenched workpiece into a high-temperature furnace, heating to 380 ℃ of 320-;
s4, dephosphorizing
And (3) putting the workpiece into an alkaline solution for descaling for 10-20min, and finally cleaning, drying and packaging the workpiece.
In a preferred embodiment, in step S1, the temperature in the annealing furnace is increased at a rate of 30-80 ℃/h, and then the annealing furnace is cooled to 350 ℃ along with the furnace, and then the annealing furnace is taken out of the furnace for air cooling.
In a preferred embodiment, in step S2, the temperature in the high-temperature furnace is increased at a rate of 100-: according to the water amount in the quenching tank, waste steel and workpieces generated during the processing of stainless steel fasteners are simultaneously placed in a high-temperature furnace to be heated to 1000 ℃, and then the waste steel is taken out and added into quenching oil when the workpieces are kept warm, so that the quenching oil is preheated to more than 40 ℃, the quenching oil is preheated by the waste steel at high temperature, substances such as dissolved oxygen in the quenching oil are consumed by reaction when the high-temperature waste steel is cooled, and the workpieces cannot react with the dissolved oxygen and other substances in the quenching oil when cooled, so that the surface components of the workpieces are ensured to be complete.
In a preferred embodiment, in step S3, the temperature in the high temperature furnace is increased at a rate of 80-120 ℃/h; in both step S2 and step S3, a methanol protective atmosphere is provided in the high-temperature furnace.
In a preferred embodiment, in step S4, the alkaline solution is an aqueous solution of sodium hydroxide with a concentration of 6% -10%.
Compared with the prior art, the invention has the beneficial effects that:
1. an annealing pretreatment process is added before tempering, so that the original structure refined grain size of the stainless steel heat-resistant steel forging can be improved, preparation is made for the subsequent tempering step, the high-temperature durability of the stainless steel heat-resistant steel forging is improved, and the tempering treatment effect is improved;
2. when the quenching and tempering treatment is carried out, oil cooling is carried out through quenching oil in quenching, waste steel for producing workpieces is synchronously heated, and the quenching oil is preheated through the high-temperature waste steel, so that substances such as dissolved oxygen in the quenching oil are consumed by reaction when the high-temperature waste steel is cooled, the workpieces cannot react with the dissolved oxygen and other substances in the quenching oil when being cooled, the surface components of the workpieces are ensured to be complete, and the surface quality of the workpieces is improved;
3. methanol protective atmosphere is arranged in the high-temperature furnaces in quenching and tempering, so that the surface of the workpiece is prevented from being oxidized by air, and the surface quality of the workpiece is further improved;
4. after modulation, the surface hardness is improved by carrying out dephosphorization treatment through alkaline solution, the service quality is high, and the service life is long.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example one
The invention provides a technical scheme that: a production process for quenching and tempering high-strength stainless steel fasteners is characterized in that an annealing pretreatment process is added before quenching and tempering, the refined grain size of the original structure of the stainless steel fasteners is improved, and the quenching and tempering treatment is carried out, and comprises the following process steps:
s1 annealing pretreatment
Putting the product into an annealing furnace for annealing treatment, heating the annealing furnace at the speed of 50 ℃/h to 740 ℃ and 760 ℃ for 2h, cooling the product to 350 ℃ and 400 ℃ along with the furnace, taking the product out, and cooling the product in the air for 2 h;
s2 quenching
Placing the pretreated workpiece into a high-temperature furnace, heating the workpiece at a speed of 120 ℃/h in the high-temperature furnace to 840-860 ℃, preserving heat for 40min, heating the workpiece to 1080-1100 ℃ and preserving heat for 2h, after the heat preservation is finished, rapidly discharging the workpiece, cooling the workpiece in a quenching tank by adopting an oil cooling mode, cooling the workpiece by adopting oil to 150-200 ℃, and taking out the workpiece for air cooling;
s3 tempering
Putting the quenched workpiece into a high-temperature furnace, heating the workpiece to the temperature of 320-plus-one 380 ℃ at the speed of 90 ℃/h in the high-temperature furnace, preserving the heat for 0.5h, then heating the workpiece to the temperature of 580-plus-one 620 ℃, preserving the heat for 1h, cooling the workpiece to the temperature of 200-plus-one 240 ℃ along with the furnace after the heat preservation is finished, and then taking out the workpiece and putting the workpiece into air for cooling for 2 h;
s4, dephosphorizing
And (3) placing the workpiece into a 7% sodium hydroxide aqueous solution for descaling for 15min, and finally cleaning, drying and packaging the workpiece.
Further, in step S2, quenching oil with a temperature of 40-60 ℃ is adopted in the quenching tank, and the quenching oil preheating method comprises the following steps: according to the water amount in the quenching tank, waste steel and workpieces generated during the processing of stainless steel fasteners are simultaneously placed in a high-temperature furnace to be heated to 1000 ℃, and then the waste steel is taken out and added into quenching oil when the workpieces are kept warm, so that the quenching oil is preheated to more than 40 ℃, the quenching oil is preheated by the waste steel at high temperature, substances such as dissolved oxygen in the quenching oil are consumed by reaction when the high-temperature waste steel is cooled, and the workpieces cannot react with the dissolved oxygen and other substances in the quenching oil when cooled, so that the surface components of the workpieces are ensured to be complete.
Further, in both step S2 and step S3, a methanol protective atmosphere is provided in the high temperature furnace.
Example two
The invention provides a technical scheme that: a production process for quenching and tempering high-strength stainless steel fasteners is characterized in that an annealing pretreatment process is added before quenching and tempering, the refined grain size of the original structure of the stainless steel fasteners is improved, and the quenching and tempering treatment is carried out, and comprises the following process steps:
s1 annealing pretreatment
Putting the product into an annealing furnace for annealing treatment, heating the annealing furnace at the speed of 70 ℃/h to 740 ℃ and 760 ℃ for 3h, then cooling the product to 350 ℃ and 400 ℃ along with the furnace, taking the product out, and cooling the product in the air for 2 h;
s2 quenching
Placing the pretreated workpiece into a high-temperature furnace, heating the workpiece at a speed of 120 ℃/h in the high-temperature furnace to 840 ℃ and 860 ℃, preserving heat for 1h, heating the workpiece to 1080 ℃ and 1100 ℃ and preserving heat for 2.5h, after the heat preservation is finished, quickly discharging the workpiece, cooling the workpiece in a quenching tank by adopting an oil cooling mode, cooling the workpiece by adopting oil to 150 ℃ and 200 ℃, and taking out the workpiece for air cooling;
s3 tempering
Putting the quenched workpiece into a high-temperature furnace, heating the workpiece to the temperature of 320-plus-one 380 ℃ at the speed of 100 ℃/h in the high-temperature furnace, preserving the heat for 0.5h, then heating the workpiece to the temperature of 580-plus-one 620 ℃, preserving the heat for 1h, cooling the workpiece to the temperature of 200-plus-one 240 ℃ along with the furnace after the heat preservation is finished, and then taking out the workpiece and putting the workpiece into air for cooling for 2 h;
s4, dephosphorizing
And (3) placing the workpiece into a 9% sodium hydroxide aqueous solution for descaling for 15min, and finally cleaning, drying and packaging the workpiece.
Further, in step S2, quenching oil with a temperature of 40-60 ℃ is adopted in the quenching tank, and the quenching oil preheating method comprises the following steps: according to the water amount in the quenching tank, waste steel and workpieces generated during the processing of stainless steel fasteners are simultaneously placed in a high-temperature furnace to be heated to 1000 ℃, and then the waste steel is taken out and added into quenching oil when the workpieces are kept warm, so that the quenching oil is preheated to more than 40 ℃, the quenching oil is preheated by the waste steel at high temperature, substances such as dissolved oxygen in the quenching oil are consumed by reaction when the high-temperature waste steel is cooled, and the workpieces cannot react with the dissolved oxygen and other substances in the quenching oil when being cooled, so that the surface components of the workpieces are ensured to be complete, and the surface quality of the workpieces is improved.
Further, in both step S2 and step S3, a methanol protective atmosphere is provided in the high temperature furnace.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (5)
1. A production process for quenching and tempering high-strength stainless steel fasteners is characterized by comprising the following process steps of:
s1 annealing pretreatment
Putting the product into an annealing furnace for annealing treatment, wherein the annealing treatment temperature is 740-760 ℃, the annealing time is 2.5-3.5h, then cooling the product to 350-400 ℃ along with the furnace, taking the product out, and putting the product into air for cooling for 2-3 h;
s2 quenching
Placing the pretreated workpiece into a high-temperature furnace, heating to 840-860 ℃, preserving heat for 0.5-1h, heating to 1080-1100 ℃ and preserving heat for 2-3h, after the heat preservation is finished, rapidly discharging, cooling in a quenching tank by adopting an oil cooling mode, cooling the oil to 150-200 ℃, and taking out for air cooling;
s3 tempering
Putting the quenched workpiece into a high-temperature furnace, heating to 380 ℃ of 320-;
s4, dephosphorizing
And (3) putting the workpiece into an alkaline solution for descaling for 10-20min, and finally cleaning, drying and packaging the workpiece.
2. The production process for quenching and tempering the high-strength stainless steel fastener according to claim 1, characterized in that: in step S1, the temperature in the annealing furnace is raised and heated at the speed of 30-80 ℃/h, and then the annealing furnace is taken out of the furnace for air cooling after being cooled to 350 ℃ along with the furnace.
3. The production process for quenching and tempering the high-strength stainless steel fastener according to claim 1, characterized in that: in step S2, the temperature in the high temperature furnace is raised and heated at the speed of 100-150 ℃/h, quenching oil with the temperature of 40-60 ℃ is adopted in the quenching tank, and the preheating method of the quenching oil comprises the following steps: according to the water amount in the quenching tank, waste steel and workpieces generated during the processing of stainless steel fasteners are simultaneously placed in a high-temperature furnace to be heated to 1000 ℃, and then the waste steel is taken out and added into quenching oil when the workpieces are kept warm, so that the quenching oil is preheated to more than 40 ℃, the quenching oil is preheated by the waste steel at high temperature, substances such as dissolved oxygen in the quenching oil are consumed by reaction when the high-temperature waste steel is cooled, and the workpieces cannot react with the dissolved oxygen and other substances in the quenching oil when cooled, so that the surface components of the workpieces are ensured to be complete.
4. The production process for quenching and tempering the high-strength stainless steel fastener according to claim 1, characterized in that: in step S3, the temperature in the high-temperature furnace is heated at a speed of 80-120 ℃/h; in both step S2 and step S3, a methanol protective atmosphere is provided in the high-temperature furnace.
5. The production process for quenching and tempering the high-strength stainless steel fastener according to claim 1, characterized in that: in step S4, the alkaline solution is an aqueous solution of sodium hydroxide with a concentration of 6% to 10%.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112522492A (en) * | 2020-10-28 | 2021-03-19 | 浙江自紧王机械有限公司 | Self-tightening nut and heat treatment process of self-tightening gasket |
| CN112921171A (en) * | 2021-01-24 | 2021-06-08 | 张会 | Heat treatment process for camshaft for general machinery |
| CN114654176A (en) * | 2022-04-21 | 2022-06-24 | 贵州航天精工制造有限公司 | Thin-wall sleeve thread machining method |
| CN116574886A (en) * | 2023-06-13 | 2023-08-11 | 宁波市齐力特钢有限公司 | Steel quenching method |
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| CN109207698A (en) * | 2018-08-27 | 2019-01-15 | 谢潇湘 | A kind of production technology for high-strength stainless steel fastening modifier treatment |
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Patent Citations (4)
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| EP0303041A2 (en) * | 1987-07-10 | 1989-02-15 | SUGITA WIRE MFG. Co., LTD. | Oil-quenched and tempered hard drawn steel wire with a shaped section, and process for producing the same |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112522492A (en) * | 2020-10-28 | 2021-03-19 | 浙江自紧王机械有限公司 | Self-tightening nut and heat treatment process of self-tightening gasket |
| CN112921171A (en) * | 2021-01-24 | 2021-06-08 | 张会 | Heat treatment process for camshaft for general machinery |
| CN114654176A (en) * | 2022-04-21 | 2022-06-24 | 贵州航天精工制造有限公司 | Thin-wall sleeve thread machining method |
| CN114654176B (en) * | 2022-04-21 | 2024-03-26 | 贵州航天精工制造有限公司 | Thin-wall sleeve thread machining method |
| CN116574886A (en) * | 2023-06-13 | 2023-08-11 | 宁波市齐力特钢有限公司 | Steel quenching method |
| CN116574886B (en) * | 2023-06-13 | 2024-05-28 | 溧阳市金昆锻压有限公司 | Steel quenching method |
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