CN113481352A - Quenching heat treatment process for wear-resisting plate - Google Patents
Quenching heat treatment process for wear-resisting plate Download PDFInfo
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- CN113481352A CN113481352A CN202110588401.3A CN202110588401A CN113481352A CN 113481352 A CN113481352 A CN 113481352A CN 202110588401 A CN202110588401 A CN 202110588401A CN 113481352 A CN113481352 A CN 113481352A
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- wear
- quenching
- temperature
- tempering
- cooling
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- 238000010791 quenching Methods 0.000 title claims abstract description 78
- 230000000171 quenching effect Effects 0.000 title claims abstract description 78
- 238000010438 heat treatment Methods 0.000 title claims abstract description 49
- 238000000034 method Methods 0.000 title claims abstract description 32
- 238000001816 cooling Methods 0.000 claims abstract description 47
- 238000005496 tempering Methods 0.000 claims abstract description 38
- 230000005540 biological transmission Effects 0.000 claims abstract description 9
- 238000005485 electric heating Methods 0.000 claims abstract description 9
- 230000006698 induction Effects 0.000 claims abstract description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- 229910000831 Steel Inorganic materials 0.000 claims description 11
- 239000010959 steel Substances 0.000 claims description 11
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 6
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims description 6
- 239000000110 cooling liquid Substances 0.000 claims description 6
- 238000004321 preservation Methods 0.000 claims description 6
- 238000009413 insulation Methods 0.000 claims description 4
- 238000004140 cleaning Methods 0.000 claims description 3
- 238000001035 drying Methods 0.000 claims description 3
- 239000003960 organic solvent Substances 0.000 claims description 3
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims 2
- 239000011780 sodium chloride Substances 0.000 claims 2
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 238000005299 abrasion Methods 0.000 abstract description 2
- 239000000463 material Substances 0.000 abstract description 2
- 239000003921 oil Substances 0.000 description 19
- 239000012267 brine Substances 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- HPALAKNZSZLMCH-UHFFFAOYSA-M sodium;chloride;hydrate Chemical compound O.[Na+].[Cl-] HPALAKNZSZLMCH-UHFFFAOYSA-M 0.000 description 5
- 238000000137 annealing Methods 0.000 description 3
- 229910000734 martensite Inorganic materials 0.000 description 3
- 230000005674 electromagnetic induction Effects 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 239000003570 air Substances 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 229910001563 bainite Inorganic materials 0.000 description 1
- 238000010923 batch production Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005307 ferromagnetism Effects 0.000 description 1
- 239000002480 mineral oil Substances 0.000 description 1
- 235000010446 mineral oil Nutrition 0.000 description 1
- 239000011490 mineral wool Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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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
- C21D1/18—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
- C21D9/0081—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for slabs; for billets
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention provides a quenching heat treatment process for an abrasion-resistant plate, which relates to the field of material heat treatment processes and comprises the following steps: preheating: the wear-resistant plate is placed on the transmission roller, the transmission roller enables the wear-resistant plate to be in an electric heating room, the temperature of the wear-resistant plate is increased to 250 ℃ and 270 ℃, and the heat is preserved for 6-10 h; a heating step: placing the wear-resistant plate under an induction coil for heating to 880 +/-10 ℃, and keeping the temperature for 65 +/-10 min; and (3) cooling: placing the heated and insulated wear-resisting plate in a quenching medium for cooling, connecting quenching oil with an external circulating cooling device through a pipeline, and ensuring the temperature of the quenching oil to be 65-70 ℃ during quenching; tempering: and tempering at a low temperature of 200-350 ℃, placing the wear-resistant plate in a motor hot room during tempering, heating to a required temperature, keeping for 5 +/-0.5 h, and taking the wear-resistant plate out of the furnace after tempering is finished, and naturally cooling to room temperature. The device has the advantages of high production efficiency and high yield.
Description
Technical Field
The invention relates to the field of material heat treatment processes, in particular to a quenching heat treatment process for an abrasion-resistant plate.
Background
Quenching is a heat treatment process in which steel is heated to a temperature above the critical temperature, held for a certain period of time, and then cooled at a rate greater than the critical cooling rate to obtain an unbalanced structure mainly composed of martensite (or bainite or single-phase austenite is obtained as necessary). Quenching is the most widely used work technology method in the heat treatment process of steel.
A metal heat treatment process of heating a metal workpiece to a suitable temperature and holding for a period of time, and then immersing the metal workpiece in a quenching medium for rapid cooling. Common quenching media are brine, water, mineral oil, air, and the like. The quenching can improve the hardness and the wear resistance of the metal workpiece, so the quenching method is widely used for various tools, dies, measuring tools and parts (such as gears, rollers, carburized parts and the like) with the required surface wear resistance. Through the matching of quenching and tempering at different temperatures, the strength, toughness reduction and fatigue strength of the metal can be greatly improved, and the matching (comprehensive mechanical properties) among the properties can be obtained to meet different use requirements. In addition, quenching can also make some special steel obtain certain physical and chemical properties, for example, quenching can make permanent magnet steel strengthen its ferromagnetism, stainless steel raise its corrosion resistance, etc. The quenching process is mainly used for steel parts.
The quenching process in the prior art has the problems that the quenching process is not suitable for mass production and the surface hardness of the workpiece after quality quenching does not reach the standard.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides a novel quenching heat treatment process for a wear-resisting plate, which can solve the technical problems in the background art.
The invention is realized by adopting the following technical scheme: a quenching heat treatment process of a wear plate is characterized by comprising the following steps: the method comprises the following steps:
and (3) cleaning the surface of the wear plate: wiping the surface of the wear-resisting plate by using isopropanol or ethanol organic solvent, and naturally drying;
preheating: the wear-resistant plate is placed on the transmission roller, the transmission roller enables the wear-resistant plate to be in an electric heating room, in the preheating step, the temperature of the wear-resistant plate is increased to 270 ℃, and the heated wear-resistant plate is subjected to heat preservation in the electric heating room for 6-10 hours;
a heating step: placing the heat-insulated wear-resistant plate under an induction coil for heating, wherein the induction coil is a plurality of frame-shaped coils, heating to 880 +/-10 ℃, and carrying out heat insulation for 65 +/-10 min;
and (3) cooling: placing the heated and insulated wear-resisting plate in a quenching medium for cooling, wherein the quenching medium is quenching oil, the quenching oil is placed in a quenching tank, the quenching oil is connected with an external circulating cooling device through a pipeline, and the temperature of the quenching oil is ensured to be 65-70 ℃ during quenching;
tempering: and tempering at a low temperature of 200-350 ℃, placing the wear-resistant plate in a motor hot room during tempering, heating to a required temperature, keeping for 5 +/-0.5 h, and taking the wear-resistant plate out of the furnace after tempering is finished, and naturally cooling to room temperature.
Preferably, in the heating step, medium-frequency constant-speed heating is adopted.
Preferably, the quenching oil is No. 20 mechanical oil.
Preferably, in the quenching step, batch wear plate quenching is adopted, and the number of wear plates subjected to single quenching is not more than 50.
Preferably, the external circulation cooling device in the cooling step comprises a cooling tank, cooling liquid is filled in the cooling tank, the cooling liquid is brine, one end of the oil pump is connected into the quenching tank through a steel pipe, the other end of the oil pump is connected with a spiral cooling pipe, the spiral cooling pipe is provided with a water inlet and a water outlet, the water outlet returns to the quenching tank through the steel pipe, and the spiral cooling pipe is placed in the brine to form a cooling loop.
Preferably, the tempering step is performed in three times, namely primary tempering, secondary tempering and tertiary tempering;
primary tempering is carried out, the temperature is kept at 220 ℃ and 250 ℃, and the temperature is kept for 2 +/-0.5 h;
performing secondary tempering, keeping the temperature at 250-270 ℃, and keeping the temperature for 2 +/-0.5 h;
and (5) tempering for three times, keeping the temperature at 320-350 ℃, and keeping the temperature for 1 +/-0.5 h.
Compared with the prior art, the process provided by the invention has the advantages that the transmission roller is adopted to drive the wear-resisting plate to pass through the electric heating insulation room for preheating once and pass through the electromagnetic induction room for heating, the automation degree is high, meanwhile, the device can also be used for batch production, and the production efficiency is high;
meanwhile, the original process is improved, the heating speed and the heat preservation time in the heating process are changed, the temperature of a quenching medium in the quenching process is changed, and cooling equipment of external circulation is added, so that the wear-resisting plate can be rapidly cooled, the nose part of a cooling curve can be rapidly avoided at 600 ℃, and enough martensite tissues can be obtained. The process can increase the yield of the quenching treatment of the wear-resisting plate.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a left side view of the induction coil;
fig. 3 is a schematic view of an external circulation cooling device.
Detailed Description
The present invention will be further described with reference to the accompanying drawings and the detailed description, and it should be noted that any combination of the embodiments or technical features described below can be used to form a new embodiment without conflict.
A quenching heat treatment process of a wear plate is characterized by comprising the following steps: the method comprises the following steps:
and (3) cleaning the surface of the wear plate: wiping the surface of the wear-resistant plate by using isopropanol or ethanol organic solvent, naturally drying the wear-resistant plate, and removing oil stains and the like on the surface of the wear-resistant plate to avoid forming carbon spots on the surface of a workpiece at high temperature; the next step is the preheating step: the preheating step and the heating step can be seen in the schematic of figures 1 and 2,
the preheating step is preliminary work before heating, the wear-resistant plate is placed on a transmission roller, the transmission roller is used for driving the wear-resistant plate to be in an electric heating room, the heating room is heated through a heating wire, meanwhile, a rock wool layer is arranged on the electric heating room for heat preservation, in the preheating step, the temperature of the wear-resistant plate is increased to 270 ℃, and the heat preservation time of the heated wear-resistant plate is 6-10 hours in the electric heating room;
a heating step: placing the heat-insulated wear-resistant plate under an induction coil for heating, wherein the induction coil is a plurality of frame-shaped coils, heating to 880 +/-10 ℃, and carrying out heat insulation for 65 +/-10 min;
and (3) cooling: placing the heated and insulated wear-resisting plate in a quenching medium for cooling, wherein the quenching medium is quenching oil, the quenching oil is placed in a quenching tank, the quenching oil is connected with an external circulating cooling device through a pipeline, and the temperature of the quenching oil is ensured to be 65-70 ℃ during quenching;
tempering: and tempering at a low temperature of 200-350 ℃, placing the wear-resistant plate in a motor hot room during tempering, heating to a required temperature, keeping for 5 +/-0.5 h, and taking the wear-resistant plate out of the furnace after tempering is finished, and naturally cooling to room temperature.
Further, in the heating step, medium-frequency constant-speed heating is adopted.
Further, the quenching oil is No. 20 mechanical oil. The mechanical oil can adopt imported Schelan mechanical oil.
Further, in the quenching step, batch wear plates are used for quenching, and the number of wear plates subjected to single quenching is not more than 50. Because need carry out the heat preservation in the heating step and handle, keep warm and can concentrate on going on in the electromagnetic induction heating room, handle a plurality of centralizations of work piece after keeping warm, have efficiently.
Further, referring to fig. 3, the external circulation cooling device in the cooling step includes a cooling tank filled with a cooling liquid, the cooling liquid is brine, one end of the oil pump is connected to the inside of the quenching tank through a steel pipe, the other end of the oil pump is connected to a spiral cooling pipe, the spiral cooling pipe is provided with a water inlet and a water outlet, the water outlet returns to the inside of the quenching tank through the steel pipe, and the spiral cooling pipe is placed in the brine to form a cooling loop.
The external circulation cooling device can rapidly cool the wear-resisting plate, and a line nose part of a cooling curve is rapidly avoided at 600 ℃ so as to obtain enough martensite structures. In order to ensure the cooling speed, the quenching medium with the mass 6-7 times of that of the workpiece is placed in a quenching tank, and the workpiece is soaked in the quenching medium when the workpiece is quenched.
Further, the tempering step is carried out in three times, namely primary tempering, secondary tempering and tertiary tempering respectively;
primary tempering is carried out, the temperature is kept at 220 ℃ and 250 ℃, and the temperature is kept for 2 +/-0.5 h;
performing secondary tempering, keeping the temperature at 250-270 ℃, and keeping the temperature for 2 +/-0.5 h;
and (5) tempering for three times, keeping the temperature at 320-350 ℃, and keeping the temperature for 1 +/-0.5 h.
The three annealing processes are carried out uninterruptedly, the temperature of the three annealing processes is gradually increased, when the temperature is increased among different temperatures, the temperature is quickly increased, and the annealing step is to increase the toughness of the workpiece.
The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention are within the protection scope of the present invention.
Claims (6)
1. A quenching heat treatment process of a wear plate is characterized by comprising the following steps: the method comprises the following steps:
and (3) cleaning the surface of the wear plate: wiping the surface of the wear-resisting plate by using isopropanol or ethanol organic solvent, and naturally drying;
preheating: the wear-resistant plate is placed on the transmission roller, the transmission roller enables the wear-resistant plate to be in an electric heating room, in the preheating step, the temperature of the wear-resistant plate is increased to 270 ℃, and the heated wear-resistant plate is subjected to heat preservation in the electric heating room for 6-10 hours;
a heating step: placing the heat-insulated wear-resistant plate under an induction coil for heating, wherein the induction coil is a plurality of frame-shaped coils, heating to 880 +/-10 ℃, and carrying out heat insulation for 65 +/-10 min;
and (3) cooling: placing the heated and insulated wear-resisting plate in a quenching medium for cooling, wherein the quenching medium is quenching oil, the quenching oil is placed in a quenching tank, the quenching oil is connected with an external circulating cooling device through a pipeline, and the temperature of the quenching oil is ensured to be 65-70 ℃ during quenching;
tempering: and tempering at a low temperature of 200-350 ℃, placing the wear-resistant plate in a motor hot room during tempering, heating to a required temperature, keeping for 5 +/-0.5 h, and taking the wear-resistant plate out of the furnace after tempering is finished, and naturally cooling to room temperature.
2. A wear plate quenching heat treatment process according to claim 1, wherein: in the heating step, medium-frequency constant-speed heating is adopted.
3. A wear plate quenching heat treatment process according to claim 1, wherein: the quenching oil is No. 20 mechanical oil.
4. A wear plate quenching heat treatment process according to claim 1, wherein: in the quenching step, the batch wear plates are used for quenching, and the number of wear plates subjected to single quenching is not more than 50.
5. A wear plate quenching heat treatment process according to claim 1, wherein: the external circulating cooling device in the cooling step comprises a cooling tank, cooling liquid is filled in the cooling tank, the cooling liquid is saline water, one end of an oil pump is connected into the quenching tank through a steel pipe, the other end of the oil pump is connected with a spiral cooling pipe, a water inlet and a water outlet are formed in the spiral cooling pipe, the water outlet returns to the quenching tank through the steel pipe, and the spiral cooling pipe is placed in the saline water to form a cooling loop.
6. A wear plate quenching heat treatment process according to claim 1, wherein: the tempering step is carried out in three times, namely primary tempering, secondary tempering and tertiary tempering respectively;
primary tempering is carried out, the temperature is kept at 220 ℃ and 250 ℃, and the temperature is kept for 2 +/-0.5 h;
performing secondary tempering, keeping the temperature at 250-270 ℃, and keeping the temperature for 2 +/-0.5 h;
and (5) tempering for three times, keeping the temperature at 320-350 ℃, and keeping the temperature for 1 +/-0.5 h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110588401.3A CN113481352A (en) | 2021-05-28 | 2021-05-28 | Quenching heat treatment process for wear-resisting plate |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110588401.3A CN113481352A (en) | 2021-05-28 | 2021-05-28 | Quenching heat treatment process for wear-resisting plate |
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| CN113481352A true CN113481352A (en) | 2021-10-08 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115109898A (en) * | 2022-06-24 | 2022-09-27 | 扬州罗尔曼轴承有限公司 | Manufacturing method of ball bearing |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101139648A (en) * | 2007-09-20 | 2008-03-12 | 吴江市天地人真空炉业有限公司 | Water cooling device for quenching oil tank |
| CN101570819A (en) * | 2009-06-18 | 2009-11-04 | 柳州金茂机械有限公司 | Heating processing technology for wear-resistant cutting board |
| CN203222600U (en) * | 2013-04-12 | 2013-10-02 | 安徽铭扬特种钢管有限公司 | Solution treatment furnace |
| CN105039674A (en) * | 2015-07-14 | 2015-11-11 | 泉州市海恩德机电科技发展有限公司 | Roller bottom type saw web quenching line |
-
2021
- 2021-05-28 CN CN202110588401.3A patent/CN113481352A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101139648A (en) * | 2007-09-20 | 2008-03-12 | 吴江市天地人真空炉业有限公司 | Water cooling device for quenching oil tank |
| CN101570819A (en) * | 2009-06-18 | 2009-11-04 | 柳州金茂机械有限公司 | Heating processing technology for wear-resistant cutting board |
| CN203222600U (en) * | 2013-04-12 | 2013-10-02 | 安徽铭扬特种钢管有限公司 | Solution treatment furnace |
| CN105039674A (en) * | 2015-07-14 | 2015-11-11 | 泉州市海恩德机电科技发展有限公司 | Roller bottom type saw web quenching line |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115109898A (en) * | 2022-06-24 | 2022-09-27 | 扬州罗尔曼轴承有限公司 | Manufacturing method of ball bearing |
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Application publication date: 20211008 |