CN102277581A - Heat treatment process of low-carbon alloy material - Google Patents
Heat treatment process of low-carbon alloy material Download PDFInfo
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Abstract
The invention discloses a heat treatment process of a low-carbon alloy material, and the heat treatment process comprises the steps of carbonitriding treatment, quenching treatment, cryogenic treatment and tempering treatment. The low-carbon alloy material, in particular 12Cr2Ni4 alloy material after the treatment through the process can obtain the surface with higher hardness and the heart part with strong toughness, and under the condition of keeping the higher toughness in a workpiece, a surface layer with high hardness and high strength can be obtained, thereby improving the abrasion resistance and the strength of the workpiece and enabling the service life of the workpiece to be in a close relationship with the toughness of the surface layer and good matching of the strong toughness of the surface layer and the heart part. After adopting the cryogenic treatment, the service life can be well prolonged and the hardness and the strength of a matrix can be improved.
Description
Technical field
The invention belongs to the thermal treatment process technology field of metallic substance, especially belong to the low-carbon alloy material heat treatment process.
Background technology
The common technology of thermal treatment process comprises technology methods such as carbonitriding, quenching, sub-zero treatment and tempering, particularly the sub-zero treatment of development recently to the processing of material after each characteristic further raising has been arranged.When metal at the thermal treatment stiffened to process of cooling, alloy wherein produces dissolving and combines and diffuse to form austenite (Austenite) with carbon, when process of cooling, owing to producing compacting, low temperature forms martensite (Martensite), and because martensitic final transition point (Mf) is very low, therefore quench cooled is to the residual a large amount of austenites of room temperature meeting, thereby hardness, wear resistance and the work-ing life of reducing metal, simultaneously cause metal cracked easily because of austenitic high fragility, moreover, also have many physicalies particularly thermal characteristics and magnetic decline.
Because austenite reaches decomposition very built on the sand under low temperature environment, make the part of original defective micropore and stress concentration produce plastic flow and become structure refinement, therefore as long as metal is placed under the ultra-low temperature surroundings, austenite wherein can change into martensite, internal stress thereby elimination.When very low temperature since tissue volume shrink, the Fe lattice parameter contracts thin and strengthens the motivating force that carbon atom is separated out, so martensitic matrix is separated out a large amount of ultra tiny carbide, these ultra tiny xln can make the intensity of material improve, and increase wear resistance and rigidity simultaneously.
Another kind of processing mode carbonitriding also is present a kind of important processing mode: carbonitriding is the process of infiltrating carbon and nitrogen to the top layer of steel simultaneously, and carbonitriding is called cyaniding again traditionally.It is wide using with carbonitriding of middle wet body and cryogenic gas carbonitriding (being gas soft nitriding) at present.The main purpose of middle wet body carbonitriding is to improve the hardness of steel, wear resistance and fatigue strength, and the cryogenic gas carbonitriding is based on nitriding, and its main purpose is to improve the wear resistance and the seizure resistance of steel.
Though with the carburizing be that the main chemical heat treatment process that infiltrates nitrogen has simultaneously overcome nitrided case hardness height to a certain extent but infiltration layer is more shallow, though and the cementation zone hardening depth is big, the shortcoming that surface hardness is lower.Use and have only gas method and salt bath method more widely.The gas carbonitriding medium is the gas mixture of carburizing agent and nitriding medium, for example drips kerosene or ethanol, acetone, logical ammonia; Drink in the neither endothermic nor exothermic type gas and increase carbon potential enriched gas and logical ammonia; Trolamine or dissolve in the pure continuous drip of urea.Carbonitriding is also quenched, is organized as martensite containing nitrogen, carboritride and residual austenite after the tempering.
At riveting machine with the low-carbon alloy material particularly in the treatment technology of 12Cr2Ni4 material, also there is not the comprehensive treatment technology scheme of system complete, the result of material processing can not reach satisfied requirement, quenching added the tempered thermal treatment process after the riveting machine of 12Cr2Ni4 adopted carbonitriding in the past, can obtain the higher hardness on surface and the obdurability of heart portion, keeping workpiece inside to have under the condition of higher toughness, obtain high rigidity, high-intensity upper layer, with the wear resistance and the intensity of raising workpiece, but also confidential relation is arranged its work-ing life with the toughness of upper layer and the obdurability good combination of upper layer and heart portion.Also there is not at present satisfied system's heat treatment technics.
Summary of the invention
The present invention discloses a kind of low-carbon alloy material heat treatment process according to the deficiencies in the prior art, the problem to be solved in the present invention provides a kind of low-carbon alloy material heat treatment process, particularly riveting machine is with the thermal treatment process of 12Cr2Ni4 parts, to improve carbonitriding highly malleablized Combined Processing result, the work-ing life of improving the riveting machine parts widely.
The present invention is achieved through the following technical solutions:
The low-carbon alloy material heat treatment process comprises carbonitriding processing, quench treatment, sub-zero treatment and temper, wherein:
Carbonitriding, handle workpiece under 850 ℃～870 ℃ conditions, speed with 180～200/per minute drips anhydrous methanol, stable lasting after 60～90 minutes, drip kerosene with the speed of 120～140/per minute and fed concentration 99.99% ammonia 60～90 minutes with 240～280 ml/min simultaneously, drip kerosene with the speed of 70～90/per minute then and feed concentration 99.99% ammonia after 150～180 minutes with 160～200 ml/min simultaneously; Be cooled to 660 ℃～720 ℃, drip anhydrous methanol with the speed of 60～90/per minute and feed concentration 99.99% ammonia 90～120 minutes to normal temperature with 80～120 ml/min simultaneously;
Quench, back workpiece oil quenching is handled in carbonitriding, 830 ℃～850 ℃ of oil quenching temperature are incubated 35～60 minutes, cooling;
Sub-zero treatment, with workpiece sub-zero treatment after the quench treatment, the treatment media liquid nitrogen, temperature-150 ℃～-160 ℃ continues 3～24 hours, takes out then to be placed under the room temperature, treats that temperature retrieval arrives room temperature;
Tempering with workpiece temper after the sub-zero treatment, at 190 ℃～210 ℃, is incubated 120 minutes, cools off in the air.
Described sub-zero treatment is from room temperature, and speed of cooling is 15 ℃～20 ℃/hour.Quench cooled is directly carried out sub-zero treatment after 7～10 minutes.
Described low-carbon alloy material is the 12Cr2Ni4 alloy material.The 12Cr2Ni4 characteristic and the scope of application: 12Cr2Ni4 intensity height, good toughness, hardening capacity are good, carburizing and quenching rear surface layer hardness and wear resistance are all good, plasticity is good during cold deformation, machinability is fair, as high loading, the repeated stress large-scale carburizing part of work down, as be subjected to the machineries such as various gears, worm gear, worm screw, axle of high loading; Its Chemical Composition mainly is: carbon C:0.13, and silicon Si:0.29, manganese Mn:0.41, sulphur S:0.008, phosphorus P:0.004, chromium Cr:1.34, nickel: 3.35, copper Cu:0.04, titanium Ti:0.01, vanadium V:0.01, molybdenum Mo:0.01; 12Cr2Ni4 mechanical property: tensile strength sigma b (MPa): 1200, yield strength σ s (MPa): 990, elongation δ 5 (%): 16, relative reduction in area ψ (%): 58, ballistic work Akv (J): 78, hardness: 243HB 245HB 245HB.
Adopt after the art breading of the present invention the low-carbon alloy material particularly the 12Cr2Ni4 alloy material have the following advantages:
1, hardness: upper layer hardness has improved 2-4HRC; 1.5-4.2HRC has improved in heart portion.
2, ballistic work: improved 50-80%.
3, bending property: significantly improve.
4, residual austenite content reduces in the upper layer tissue, and martensite and carbide increase, and carbide small and dispersed uniform distribution, thereby have improved obdurability.Residual austenite content reduces to some extent in the core structure, and corresponding martensite increases, thereby has improved matrix hardness and intensity.
5, prolong 50%-70% work-ing life.Ordinary process is handled the average access times of same material general 20,000 times, and access times are about 2.9 ten thousand to 3.5 ten thousand times after the process modification of the present invention.
In sum, low-carbon alloy material after the art breading of the present invention particularly 12Cr2Ni4 alloy material can obtain the higher hardness on surface and the obdurability of heart portion, keeping workpiece inside to have under the condition of higher toughness, obtain high rigidity, high-intensity upper layer, to improve the wear resistance and the intensity of workpiece, the obdurability good combination of the toughness of its work-ing life and upper layer and upper layer and heart portion has confidential relation.Can well prolong work-ing life after adopting sub-zero treatment, improve matrix hardness and intensity.
Description of drawings
Fig. 1 organizes micro-enlarged photograph by the 12Cr2Ni4 alloy material upper layer of art breading of the present invention.
Fig. 2 is the micro-enlarged photograph of 12Cr2Ni4 alloy material core structure by art breading of the present invention.
Fig. 3 is that the 12Cr2Ni4 alloy material upper layer of traditional technology processing comparative example is organized micro-enlarged photograph.
Fig. 4 is the micro-enlarged photograph of 12Cr2Ni4 alloy material core structure that traditional technology is handled comparative example.
Fig. 5 is a carbonitriding technology flow process conditional parameter table of the present invention.
Embodiment
The present invention is further described below in conjunction with embodiment, and embodiment is to the further specifying of the principle of the invention, and does not limit the present invention in any way, or similar techniques identical with the present invention all do not exceed the scope of protection of the invention.
Embodiment 1
This example adopts thermal treatment process of the present invention.
Material is prepared, and gets the riveting machine that the 12Cr2Ni4 alloy material is made, and removes surface irregularities.
Thermal treatment, the riveting machine that above-mentioned 12Cr2Ni4 alloy material is made follows these steps to handle,
1, carbonitriding, handle workpiece under 850 ℃～870 ℃ conditions, speed with 180～200/per minute drips anhydrous methanol, stable lasting after 60～90 minutes, drip kerosene with the speed of 120～140/per minute and fed concentration 99.99% ammonia 60～90 minutes with 240～280 ml/min simultaneously, drip kerosene with the speed of 70～90/per minute then and feed concentration 99.99% ammonia after 150～180 minutes with 160～200 ml/min simultaneously; Be cooled to 660 ℃～720 ℃, drip anhydrous methanol with the speed of 60～90/per minute and feed concentration 99.99% ammonia 90～120 minutes to normal temperature with 80～120 ml/min simultaneously; Described carbonitriding this area can be represented with following table:
2, quench, back workpiece oil quenching is handled in carbonitriding, 830 ℃～850 ℃ of oil quenching temperature are incubated 35～60 minutes, cooling;
3, sub-zero treatment, with workpiece sub-zero treatment after the quench treatment, the treatment media liquid nitrogen, temperature-150 ℃～-160 ℃ continues 3～24 hours;
4, tempering with workpiece temper after the sub-zero treatment, at 190 ℃～210 ℃, is incubated 120 minutes, cools off in the air.
Can be by from room temperature when sub-zero treatment, speed of cooling is carried out with 15 ℃-20 ℃/hour.
Handling laggard line correlation detects.
Comparative example
Choose with embodiment 1 identical materials part and heat-treat by traditional method, concrete steps are: 1, carbonitriding; 2, quench; 3, tempering.Each step condition can adopt typical conditions, for relatively, and the condition that this routine carbonitriding, quenching and tempering employing and embodiment 1 are identical.
Handling laggard line correlation detects.
Comparative result is as follows:
Hardness HRC:(sees Table 1)
The hardness value data of two kinds of treatment process of table 1.
Impelling strength: (seeing Table 2)
The ballistic work data of two kinds of treatment process of table 2.
Flexural strength: (seeing Table 3)
The crooked test sample is a rectangle in this research, becomes bend specimen by materials processing, again each sample is carried out carbonitriding thermal treatment, carries out then carrying out crooked test again after above two kinds of art breading.During crooked test, rectangular specimen is placed on span L
sCarrying out three-point bending on the bearing of=80mm loads.
The flexural strength data of two kinds of treatment process of table 3.
In conjunction with the micro-enlarged photograph of contrast the present invention example, can know that the 12Cr2Ni4 alloy material hardness after the present invention handles: upper layer hardness has improved 2-4HRC with comparative example; 1.5-4.2HRC has improved in heart portion.Ballistic work has improved 50-80%.Bending property significantly improves.Residual austenite content reduces in the upper layer tissue, and martensite and carbide increase, and carbide small and dispersed uniform distribution, thereby have improved obdurability.Residual austenite content reduces to some extent in the core structure, and corresponding martensite increases, thereby has improved matrix hardness and intensity.
Prolong 50%-70% work-ing life.The average access times of overcoat are general 20,000 times in original technology, and access times are about 2.9 ten thousand to 3.5 ten thousand times after the process process modification.
Claims (3)
1. a low-carbon alloy material heat treatment process comprises carbonitriding processing, quench treatment, sub-zero treatment and temper, it is characterized in that:
Carbonitriding, handle workpiece under 850 ℃～870 ℃ conditions, speed with 180～200/per minute drips anhydrous methanol, stable lasting after 60～90 minutes, drip kerosene with the speed of 120～140/per minute and fed concentration 99.99% ammonia 60～90 minutes with 240～280 ml/min simultaneously, drip kerosene with the speed of 70～90/per minute then and feed concentration 99.99% ammonia after 150～180 minutes with 160～200 ml/min simultaneously; Be cooled to 660 ℃～720 ℃, drip anhydrous methanol with the speed of 60～90/per minute and feed concentration 99.99% ammonia 90～120 minutes to normal temperature with 80～120 ml/min simultaneously;
Quench, back workpiece oil quenching is handled in carbonitriding, 830 ℃～850 ℃ of oil quenching temperature are incubated 35～60 minutes, cooling;
Sub-zero treatment, with workpiece sub-zero treatment after the quench treatment, the treatment media liquid nitrogen, temperature-150 ℃～-160 ℃ continues 3～24 hours, takes out then to be placed under the room temperature, treats that temperature retrieval arrives room temperature;
Tempering with workpiece temper after the sub-zero treatment, at 190 ℃～210 ℃, is incubated 120 minutes, cool off in the air.
2. low-carbon alloy material heat treatment process according to claim 1 is characterized in that: described sub-zero treatment is from room temperature, and speed of cooling is 15 ℃～20 ℃/hour.
3. low-carbon alloy material heat treatment process according to claim 1 and 2 is characterized in that: described low-carbon alloy material is the 12Cr2Ni4 alloy material.
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103447782A (en) * | 2013-09-12 | 2013-12-18 | 昆山奥德鲁自动化技术有限公司 | Machining method of lathe spindle |
| CN103555923A (en) * | 2013-11-01 | 2014-02-05 | 瓦房店凯威精工轴承制造有限公司 | Precision bearing cold and heat treatment technological method |
| CN103924248A (en) * | 2014-04-24 | 2014-07-16 | 鑫光热处理工业(昆山)有限公司 | Carbonitriding quenching process for car seat adjuster component |
| CN105886941A (en) * | 2016-06-16 | 2016-08-24 | 汤海涛 | Non-quenched and tempered composite shaft part |
| CN105970150A (en) * | 2016-07-01 | 2016-09-28 | 兴化东华齿轮有限公司 | Super carbonitriding process |
| CN106048509A (en) * | 2016-07-01 | 2016-10-26 | 兴化东华齿轮有限公司 | Low-temperature nitrocarburizing technology for chain wheels |
| CN107299204A (en) * | 2017-03-31 | 2017-10-27 | 西南大学 | A kind of processing method of raising 20CrMnMo hardness of steel |
| CN108411093A (en) * | 2018-03-26 | 2018-08-17 | 湖南特科能热处理有限公司 | A kind of heat treatment process reducing transfer-case idle shaft gear shifting quadrant texturing |
| CN110714181A (en) * | 2019-10-16 | 2020-01-21 | 中国航发中传机械有限公司 | Heat treatment method of lubricating oil pump gear |
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| CN115198059A (en) * | 2022-06-09 | 2022-10-18 | 太原理工大学 | Magnetic field cryogenic treatment method for increasing wear resistance of 18CrNiMo7-6 carburizing steel |
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Cited By (18)
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| CN103447782A (en) * | 2013-09-12 | 2013-12-18 | 昆山奥德鲁自动化技术有限公司 | Machining method of lathe spindle |
| CN103555923A (en) * | 2013-11-01 | 2014-02-05 | 瓦房店凯威精工轴承制造有限公司 | Precision bearing cold and heat treatment technological method |
| CN103924248A (en) * | 2014-04-24 | 2014-07-16 | 鑫光热处理工业(昆山)有限公司 | Carbonitriding quenching process for car seat adjuster component |
| CN105886941A (en) * | 2016-06-16 | 2016-08-24 | 汤海涛 | Non-quenched and tempered composite shaft part |
| CN106048509B (en) * | 2016-07-01 | 2018-03-09 | 兴化东华齿轮有限公司 | A kind of sprocket wheel low-temperature nitrocarburizing technique |
| CN105970150B (en) * | 2016-07-01 | 2018-03-09 | 兴化东华齿轮有限公司 | A kind of super C N co-penetration technologies |
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| CN106048509A (en) * | 2016-07-01 | 2016-10-26 | 兴化东华齿轮有限公司 | Low-temperature nitrocarburizing technology for chain wheels |
| CN107299204A (en) * | 2017-03-31 | 2017-10-27 | 西南大学 | A kind of processing method of raising 20CrMnMo hardness of steel |
| CN108411093A (en) * | 2018-03-26 | 2018-08-17 | 湖南特科能热处理有限公司 | A kind of heat treatment process reducing transfer-case idle shaft gear shifting quadrant texturing |
| CN110714181B (en) * | 2019-10-16 | 2022-06-14 | 中国航发中传机械有限公司 | Heat treatment method of lubricating oil pump gear |
| CN110714181A (en) * | 2019-10-16 | 2020-01-21 | 中国航发中传机械有限公司 | Heat treatment method of lubricating oil pump gear |
| CN112157929A (en) * | 2020-09-25 | 2021-01-01 | 湖南科嘉新材料有限公司 | Hot-press forming and demoulding method for short fiber reinforced carbon/resin composite material |
| CN112157929B (en) * | 2020-09-25 | 2022-07-08 | 湖南科嘉新材料有限公司 | Hot-press forming and demoulding method for short fiber reinforced carbon/resin composite material |
| CN115198059A (en) * | 2022-06-09 | 2022-10-18 | 太原理工大学 | Magnetic field cryogenic treatment method for increasing wear resistance of 18CrNiMo7-6 carburizing steel |
| CN115198059B (en) * | 2022-06-09 | 2023-09-08 | 太原理工大学 | Magnetic field cryogenic treatment method for increasing wear resistance of 18CrNiMo7-6 carburizing steel |
| CN117144288A (en) * | 2023-10-24 | 2023-12-01 | 中国科学院力学研究所 | Chemical heat treatment process for surface modified layer steel |
| CN117144288B (en) * | 2023-10-24 | 2024-01-30 | 中国科学院力学研究所 | Chemical heat treatment process for surface modified layer steel |
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