CN102888610A - Thermal treatment method for internal spline gear with small modulus - Google Patents

Thermal treatment method for internal spline gear with small modulus Download PDF

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Publication number
CN102888610A
CN102888610A CN2012104093970A CN201210409397A CN102888610A CN 102888610 A CN102888610 A CN 102888610A CN 2012104093970 A CN2012104093970 A CN 2012104093970A CN 201210409397 A CN201210409397 A CN 201210409397A CN 102888610 A CN102888610 A CN 102888610A
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China
Prior art keywords
spline
quenching
carburizing
plug
insulation
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Pending
Application number
CN2012104093970A
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Chinese (zh)
Inventor
曾西军
师玉英
李海宏
辛玉武
徐奉鑫
张琼
张宇慧
刘薇
钱钰
崔雪莹
邵秀云
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AVIC Harbin Dongan Engine Group Co Ltd
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AVIC Harbin Dongan Engine Group Co Ltd
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Priority to CN2012104093970A priority Critical patent/CN102888610A/en
Publication of CN102888610A publication Critical patent/CN102888610A/en
Pending legal-status Critical Current

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Abstract

The invention discloses a thermal treatment method for an internal spline gear with small modulus. The method has a principle similar to a press quenching and is characterized in that: a core rod with the size consistent to the size of a spline internal hole is adopted, as the size of the spline internal hole is basically consistent to the size of the core rod, the core rod is inserted into the spline internal hole when a spline is heated to the quenching temperature and is taken out of a furnace for quenching; due to the principle of expansion with heat and contraction with cold, the spline and the core rod are tightly pressed together after oil feeding; due to the limitation of the size and the shape of the core rod, the deformation is limited in a defined range. According to the thermal treatment method, a controllable atmosphere heat treatment furnace is adopted for carburization; and through controlling furnace temperature, insulation time and carbon potential and selecting a proper core rod for quenching thermal treatment, the deformation requirement after carburization and quenching of the spline internal hole can be met. Meanwhile, the grinding step is omitted, the use requirements of a carburized layer and the hardness of the core part of a part can be ensured.

Description

Little modulus inside spline wheel gear heat treating method
Technical field
The present invention relates to a kind of heat treating method, especially a kind of little modulus inside spline wheel gear heat treating method.
Background technology
9310 steel are a kind of materials commonly used in the aviation, little modulus inside spline wheel gear by 9310 steel makings not only has outer rotor but also contain internal spline, and its internal spline has the thinner characteristics of through-hole diameter little (diameter is less than 20mm), modulus little (modulus is not more than 1), tooth depth and transverse tooth thickness.Internal spline and outer rotor all are to adopt thermo-chemical treatment because requiring to have preferably wear resistance usually, and the mode that carburizing, carbonitriding are arranged commonly used reaches the performance of design, satisfies service requirements.Quenching strain is in various degree arranged after gear and the carburizing of internal spline class part at present, in order to control this distortion, all is to leave certain cementation zone surplus usually, controls quenching strain by the mode of grinding, reaches the purpose of use.But the method control distortion by grinding is difficult to guarantee that part case depth and heart section satisfy hardness requirement.
Summary of the invention
The purpose of this invention is to provide a kind of little modulus inside spline wheel gear heat treating method, guarantee that the Internal Hole Deformation amount is controlled at more among a small circle behind the carburizing and quenching in, and cementation zone and centre hardness satisfy service requirements.
Main technique route of the present invention is:
(1) prepares 9310 steel parts, gear parts is machined to requires size;
(2) part is carried out modifier treatment in resistance furnace, temperature is 820 ± 6 ℃, insulation 90~100min, and then then oil cooling is incubated 4~4.5h when temperature is 150 ± 10 ℃, and air cooling is come out of the stove;
(3) the processing internal spline is to requiring size;
(4) according to the internal spline dimensioned plug that processes, mandrel material is other material that 9310 steel or quenching and tempering hardness are higher than 9310 steel, and plug need carry out modifier treatment, and plug and spline endoporus tolerance on fit are ± 0.005mm;
(5) with carburizing after the non-carburizing face copper facing protection of part, equipment is the controlled atmosphere cementing furnace, holding temperature is 900 ± 6 ℃, and the carbon potential that the fs adopts is between 0.30~0.40%C, insulation 30~40min, the carbon potential that subordinate phase adopts is between 0.95~0.98%C, insulation 0.5~1h, furnace cooling to 815 after carburizing finishes ± 6 ℃, carbon potential is 0.90~0.95%C, insulation 30~40min, furnace cooling;
(6) with part high tempering in controlled atmosphere generator, temperature is 621 ± 14 ℃, insulation 3~3.5h, and air cooling is come out of the stove;
(7) the protection copper layer of the non-carburizing face of removal;
(8) part is changed in the stove of turning quench, its parameters of quenching is 815 ± 10 ℃ of holding temperatures, and soaking time 105~120min puts into spline endoporus place with plug when part is come out of the stove, and enters at once afterwards oil cooling;
(9) part is taken out from quenching oil after, apply certain pressure with pressing machine plug withdrawed from;
(10) part is carried out ice-cold processing, equipment is refrigerator, holding temperature is≤and-80 ℃, soaking time is 4~4.5h; Part after the ice-cold processing is put into air circulating oven and is carried out low-temperaturetempering, and holding temperature is 150 ± 6 ℃, and soaking time is 4~4.5h, air cooling;
(11) final inspection.
The principle of the invention is similar to press quenching.Adopt the plug with spline endoporus consistent size, because size and the plug size of spline endoporus are basically identical, spline is when being heated to quenching temperature and coming out of the stove quenching, plug is inserted spline endoporus place, owing to expanding with heat and contract with cold, enter the rear spline of oil and plug and be pressed together, be subjected to the restriction of plug shape and size, with limit deformation within the limits prescribed.
The present invention adopts atmosphere controlled heat treatment furnace to carry out carburizing, by the control to furnace temperature, soaking time, carbon potential, chooses suitable plug and carries out quenching heat treatment.Guaranteed the deformation requirements behind the spline endoporus carburizing and quenching.Simultaneously, because the present invention has cancelled the grinding step, therefore guaranteed the service requirements of cementation zone and the centre hardness of part.
Embodiment
The concrete steps of internal spline carburizing and quenching deformation control method are as follows:
(1) prepares 9310 steel parts, gear parts is machined to requires size;
(2) part is carried out modifier treatment in resistance furnace, temperature is 820 ± 6 ℃, insulation 90~100min, and then then oil cooling is incubated 4~4.5h when temperature is 150 ± 10 ℃, and air cooling is come out of the stove;
(3) the processing internal spline is to requiring size;
(4) according to the internal spline dimensioned plug that processes, mandrel material is other material that 9310 steel or quenching and tempering hardness are higher than 9310 steel, and plug need carry out modifier treatment, and plug and spline endoporus tolerance on fit are ± 0.005mm;
(5) with carburizing after the non-carburizing face copper facing protection of part, equipment is the controlled atmosphere cementing furnace, holding temperature is 900 ± 6 ℃, and the carbon potential that the fs adopts is between 0.30~0.40%C, insulation 30~40min, the carbon potential that subordinate phase adopts is between 0.95~0.98%C, insulation 0.5~1h, furnace cooling to 815 after carburizing finishes ± 6 ℃, carbon potential is 0.90~0.95%C, insulation 30~40min, furnace cooling;
(6) with part high tempering in controlled atmosphere generator, temperature is 621 ± 14 ℃, insulation 3~3.5h, and air cooling is come out of the stove;
(7) the protection copper layer of the non-carburizing face of removal;
(8) part is changed in the stove of turning quench, its parameters of quenching is 815 ± 10 ℃ of holding temperatures, and soaking time 105~120min puts into spline endoporus place with plug when part is come out of the stove, and enters at once afterwards oil cooling;
(9) part is taken out from quenching oil after, apply certain pressure with pressing machine plug withdrawed from;
(10) part is carried out ice-cold processing, equipment is refrigerator, holding temperature is≤and-80 ℃, soaking time is 4~4.5h; Part after the ice-cold processing is put into air circulating oven and is carried out low-temperaturetempering, and holding temperature is 150 ± 6 ℃, and soaking time is 4~4.5h, air cooling;
(11) final inspection.
Embodiment
The material that certain engine oil pump gear is selected is 9310 steel, the inner band of this gear spline, and the spline diameter of bore is Φ 11.7mm~Φ 11.9mm, tooth depth, transverse tooth thickness is thinner is 1~2mm.The carburizing parameter and the deformation requirements that require are: effective case depth 0.25~0.51mm, surface hardness HRA81~83, centre hardness HRC33~41.The spline endoporus is no longer processed behind the carburizing and quenching.Be Mp=10.765 before the size carburizing between the roller of spline tooth, require deflection after the carburizing in the 0.05mm scope.
Concrete carburizing and quenching step is:
(1) prepares 9310 steel parts, gear parts is machined to requires size;
(2) part is carried out modifier treatment in resistance furnace, temperature is 820 ℃, insulation 100min, and then then oil cooling is incubated 4h when temperature is 150 ℃, and air cooling is come out of the stove;
(3) the processing internal spline is to requiring size;
(4) according to the internal spline dimensioned plug that processes, mandrel material is other material that 9310 steel or quenching and tempering hardness are higher than 9310 steel, and plug need carry out modifier treatment, and plug and spline endoporus tolerance on fit are ± 0.005mm;
(5) with carburizing after the non-carburizing face copper facing protection of part, equipment is the controlled atmosphere cementing furnace, holding temperature is 900 ℃, and the carbon potential that the fs adopts is 0.40%, insulation 35min, the carbon potential that subordinate phase adopts is 0.96%, insulation 0.8h, furnace cooling to 815 ℃ after carburizing finishes, carbon potential is 0.95%, insulation 35min, furnace cooling;
(6) with part high tempering in controlled atmosphere generator, temperature is 621 ℃, insulation 3h, and air cooling is come out of the stove;
(7) the protection copper layer of the non-carburizing face of removal;
(8) part is changed in the stove of turning quench, its parameters of quenching is 815 ℃ of holding temperatures, and soaking time 110min puts into spline endoporus place with plug when part is come out of the stove, and enters at once afterwards oil cooling;
(9) part is taken out from quenching oil after, apply certain pressure with pressing machine plug withdrawed from;
(10) part is carried out ice-cold processing, equipment is refrigerator, and holding temperature is-80 ℃, and soaking time is 4h; Part after the ice-cold processing is put into air circulating oven and is carried out low-temperaturetempering, and holding temperature is 150 ℃, and soaking time is 4h, air cooling;
(11) final inspection: Mp is Φ 10.735mm behind the carburizing and quenching, and endoporus size distortion amount is 0.03mm, and the more even zero draft of distortion.The effective case depth of part tooth top is 0.46mm, and surface hardness is HRA82.0, centre hardness HRC39.The microstructure of the surface microhardness of material and heart section meets the correlation technique requirement of corresponding air standard 5492 " carburizing of aviation steelwork, carbonitriding microstructure examination standard ".

Claims (1)

1. one kind little modulus inside spline wheel gear heat treating method is characterized in that, the concrete steps of described method are:
(1) prepares 9310 steel parts, gear parts is machined to requires size;
(2) part is carried out modifier treatment in resistance furnace, temperature is 820 ± 6 ℃, insulation 90~100min, and then then oil cooling is incubated 4~4.5h when temperature is 150 ± 10 ℃, and air cooling is come out of the stove;
(3) the processing internal spline is to requiring size;
(4) according to the internal spline dimensioned plug that processes, mandrel material is other material that 9310 steel or quenching and tempering hardness are higher than 9310 steel, and plug need carry out modifier treatment, and plug and spline endoporus tolerance on fit are ± 0.005mm;
(5) with carburizing after the non-carburizing face copper facing protection of part, equipment is the controlled atmosphere cementing furnace, holding temperature is 900 ± 6 ℃, and the carbon potential that the fs adopts is between 0.30~0.40%C, insulation 30~40min, the carbon potential that subordinate phase adopts is between 0.95~0.98%C, insulation 0.5~1h, furnace cooling to 815 after carburizing finishes ± 6 ℃, carbon potential is 0.90~0.95%C, insulation 30~40min, furnace cooling;
(6) with part high tempering in controlled atmosphere generator, temperature is 621 ± 14 ℃, insulation 3~3.5h, and air cooling is come out of the stove;
(7) adopt chemical process to remove the protection copper layer of non-carburizing face;
(8) part is changed in the stove of turning quench, its parameters of quenching is 815 ± 10 ℃ of holding temperatures, and soaking time 105~120min puts into spline endoporus place with plug when part is come out of the stove, and enters at once afterwards oil cooling;
(9) part is taken out from quenching oil after, apply certain pressure with pressing machine plug withdrawed from;
(10) part is carried out ice-cold processing, equipment is refrigerator, holding temperature is≤and-80 ℃, soaking time is 4~4.5h; Part after the ice-cold processing is put into air circulating oven and is carried out low-temperaturetempering, and holding temperature is 150 ± 6 ℃, and soaking time is 4~4.5h, air cooling;
(11) final inspection.
CN2012104093970A 2012-10-24 2012-10-24 Thermal treatment method for internal spline gear with small modulus Pending CN102888610A (en)

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Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103540945A (en) * 2013-10-21 2014-01-29 哈尔滨东安发动机(集团)有限公司 Thin-walled part nitridation deformation control method
CN103556105A (en) * 2013-10-21 2014-02-05 哈尔滨东安发动机(集团)有限公司 Carburization method of 10CrNi2Mo3Cu2V material
CN103643022A (en) * 2013-12-05 2014-03-19 天水星火机床有限责任公司 Method for preventing gear wall deformation during gear quenching
CN103710516A (en) * 2013-12-31 2014-04-09 苏州亚太金属有限公司 Large-diameter small-modulus gear quenching process
CN104372157A (en) * 2014-11-14 2015-02-25 哈尔滨东安发动机(集团)有限公司 Thermal treatment deformation control method for duplicate spiral bevel gear
CN104805393A (en) * 2015-05-26 2015-07-29 重庆银雁科技有限公司 Multi-purpose furnace carburizing and quenching process for automobile door lock catches
CN105386043A (en) * 2015-11-13 2016-03-09 哈尔滨东安发动机(集团)有限公司 Method for preventing excessive seepage of 16Cr3NiWMoVNbE material narrow-tooth-shaped component tooth crest
CN105386044A (en) * 2015-11-13 2016-03-09 哈尔滨东安发动机(集团)有限公司 Method for solving problem of excessive seepage of 18CrNi4A material narrow-tooth-shaped component tooth crest
CN106555153A (en) * 2015-09-29 2017-04-05 常州兰翔机械有限责任公司 A kind of blade mounting seat heat treatment method
CN106555154A (en) * 2015-09-29 2017-04-05 常州兰翔机械有限责任公司 A kind of driven gear heat treatment method
CN108193043A (en) * 2017-11-27 2018-06-22 江阴市永兴机械制造有限公司 A kind of low module Thermal treatment method for internal spline gear
CN108247304A (en) * 2018-01-12 2018-07-06 中国航发哈尔滨东安发动机有限公司 The method for promoting teeth directional precision after internal spline is heat-treated
CN108265170A (en) * 2018-01-12 2018-07-10 中国航发哈尔滨东安发动机有限公司 The method for promoting profile accuracy after internal spline is heat-treated
CN108895145A (en) * 2018-07-17 2018-11-27 湖南南方宇航高精传动有限公司 A kind of novel wind-powered electricity generation main-gear box internal spline structure
CN109207903A (en) * 2018-08-29 2019-01-15 浙江亚美力汽车部件有限公司 A kind of excavator guide valve fitment anti-carburizi ng technique
CN109487069A (en) * 2018-12-31 2019-03-19 兴化东华齿轮有限公司 A kind of heat treatment method of ring gear control heat-treatment distortion
CN110355538A (en) * 2019-06-11 2019-10-22 北京理工大学 The processing method of the planetary reduction gear ring gear of bio-robot
CN110565043A (en) * 2019-09-24 2019-12-13 重庆齿轮箱有限责任公司 Method for processing gears with different modules on same part
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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CN103556105A (en) * 2013-10-21 2014-02-05 哈尔滨东安发动机(集团)有限公司 Carburization method of 10CrNi2Mo3Cu2V material
CN103540945B (en) * 2013-10-21 2015-07-01 哈尔滨东安发动机(集团)有限公司 Thin-walled part nitridation deformation control method
CN103556105B (en) * 2013-10-21 2015-12-09 哈尔滨东安发动机(集团)有限公司 The method for carburizing of 10CrNi2Mo3Cu2V material
CN103643022A (en) * 2013-12-05 2014-03-19 天水星火机床有限责任公司 Method for preventing gear wall deformation during gear quenching
CN103710516A (en) * 2013-12-31 2014-04-09 苏州亚太金属有限公司 Large-diameter small-modulus gear quenching process
CN103710516B (en) * 2013-12-31 2016-02-03 苏州亚太金属有限公司 A kind of major diameter fine module gear quenching technology
CN104372157A (en) * 2014-11-14 2015-02-25 哈尔滨东安发动机(集团)有限公司 Thermal treatment deformation control method for duplicate spiral bevel gear
CN104372157B (en) * 2014-11-14 2018-11-20 哈尔滨东安发动机(集团)有限公司 Duplex spiral bevel gear method for controlling heat treatment deformation
CN104805393A (en) * 2015-05-26 2015-07-29 重庆银雁科技有限公司 Multi-purpose furnace carburizing and quenching process for automobile door lock catches
CN108913850A (en) * 2015-09-29 2018-11-30 中国航发常州兰翔机械有限责任公司 It is easy to the aero-engine blade mounting base produced in batches
CN106555153A (en) * 2015-09-29 2017-04-05 常州兰翔机械有限责任公司 A kind of blade mounting seat heat treatment method
CN106555154A (en) * 2015-09-29 2017-04-05 常州兰翔机械有限责任公司 A kind of driven gear heat treatment method
CN108950466A (en) * 2015-09-29 2018-12-07 中国航发常州兰翔机械有限责任公司 The aero-engine blade mounting base of tempered sorbite is not will form
CN106555153B (en) * 2015-09-29 2018-09-21 中国航发常州兰翔机械有限责任公司 A kind of blade mounting base heat treatment method
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CN105386044B (en) * 2015-11-13 2018-03-09 哈尔滨东安发动机(集团)有限公司 A kind of narrow profiled parts tooth top of solution 18CrNi4A materials crosses the method oozed
CN105386044A (en) * 2015-11-13 2016-03-09 哈尔滨东安发动机(集团)有限公司 Method for solving problem of excessive seepage of 18CrNi4A material narrow-tooth-shaped component tooth crest
CN105386043A (en) * 2015-11-13 2016-03-09 哈尔滨东安发动机(集团)有限公司 Method for preventing excessive seepage of 16Cr3NiWMoVNbE material narrow-tooth-shaped component tooth crest
CN108193043A (en) * 2017-11-27 2018-06-22 江阴市永兴机械制造有限公司 A kind of low module Thermal treatment method for internal spline gear
CN108265170A (en) * 2018-01-12 2018-07-10 中国航发哈尔滨东安发动机有限公司 The method for promoting profile accuracy after internal spline is heat-treated
CN108247304A (en) * 2018-01-12 2018-07-06 中国航发哈尔滨东安发动机有限公司 The method for promoting teeth directional precision after internal spline is heat-treated
CN108895145A (en) * 2018-07-17 2018-11-27 湖南南方宇航高精传动有限公司 A kind of novel wind-powered electricity generation main-gear box internal spline structure
CN109207903A (en) * 2018-08-29 2019-01-15 浙江亚美力汽车部件有限公司 A kind of excavator guide valve fitment anti-carburizi ng technique
CN109487069A (en) * 2018-12-31 2019-03-19 兴化东华齿轮有限公司 A kind of heat treatment method of ring gear control heat-treatment distortion
CN110355538A (en) * 2019-06-11 2019-10-22 北京理工大学 The processing method of the planetary reduction gear ring gear of bio-robot
CN110565043A (en) * 2019-09-24 2019-12-13 重庆齿轮箱有限责任公司 Method for processing gears with different modules on same part
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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