Low pressure carburizing process for aviation bearing steel

doi:10.13251/j.issn.0254-6051.2020.01.001

Abstract

Abstract: Effect of low-pressure carburizing on the microstructure and properties of aviation bearing steel was studied by using Rockwell hardness tester, Vickers hardness tester and optical microscopy. The results show that a continuous network of grain boundary carbides is observed after carburizing, but it gradually changes to be discontinuous during the subsequent heat treatment process. The effective hardening layer gradually increases from 0.45 mm after carburizing to the neighboring region of the preset value (0.77 mm). The “bow” phenomenon in hardness curve of carburizing layer gradually eliminates, and the hardness curve becomes smoother from the carburized surface to the core. After carburizing, the hardness of the experimental steel is increased by 11 HRC compared with the original hardness. After the whole heat treatment process of vacuum and low pressure carburizing process, the surface hardness is further increased by 16-18 HRC.

Key words: heat treatment, vacuum low pressure carburization, aviation bearing steel, surface hardness, reticular carbide, retained austenite

CLC Number:

TG156.8⁺1

Wang Hui, Wang Haojie, Jia Tao, Tian Yong, Wang Zhaodong. Low pressure carburizing process for aviation bearing steel[J]. HTM, 2020, 45(1): 1-5.

References

[1]Korecki Maciej. 低压真空渗碳PreNitLPC技术[C]//第十一次全国热处理大会. 2015: 170-171.
[2]Gawronski Z, Malasinski A, Sawicki J. Elimination of galvanic copper plating process used in hardening of concentionally carburizing gear wheels[J]. International Journal of Automotive Technology, 2010, 11(1): 127-131.
[3]Kazuyuki Yada, Osamu Watanabe. Reactive flow simulation of vacuum carburizing by acetylene gas[J]. Computers and Fluids, 2013, 79: 65-76.
[4]张文汉. V-Nb微合金化齿轮钢及其热处理工艺和力学性能的研究[D]. 武汉: 武汉科技大学, 2007: 6-7.
Zhang Wenhan. A study on fabrication, heat-treatments and mechanical properties of V-Nb microalloyed gear steel[D]. Wuhan: Wuhan University of Science and Technology, 2007: 6-7.
[5]陈鼎, 陈吉华, 严红革. 深冷处理原理及其在工业上的应用[J]. 兵器材料科学与工程, 2003, 26(3): 68-72.
Chen Ding, Chen Jihua, Yan Hongge. Mechanism & industrial applications of cryogenic treatment[J]. Ordance of Material Science and Engineering, 2003, 26(3): 68-72.
[6]黎文献, 龚浩然. 金属材料的深冷处理[J]. 材料导报, 2000, 14(3): 16-18.
Li Wenxian, Gong Haoran. Deep cryogenic treatment of metal materials[J]. Materials Review, 2000, 14(3): 16-18.
[7]肖茂果, 李东辉, 吕新杨. 热处理对高Cr-Co-Mo轴承钢组织与性能的影响[J]. 材料热处理学报, 2018, 38(8): 75-81.
Xiao Maoguo, Li Donghui, Lü Xinyang. Effects of heat treatment on microstructure and properties of a high Cr-Co-Mo alloyed heat resistant bearing steel[J]. Transactions of Materials and Heat Treatment, 2018, 38(8): 75-81.
[8]马永庆, 高洪涛, 章晓静. CrWMn钢中添加微量Mo对网状碳化物的影响[J]. 金属热处理, 2018, 43(4): 34-38.
Ma Yongqing, Gao Hongtao, Zhang Xiaojing. Effect of adding little Mo on network carbide in CrWMn steel[J]. Heat Treatment of Metals, 2018, 43(4): 34-38.
[9]马永庆, 章晓静, 梁玉芬. Cr-W-Mo-V高合金中高碳钢的显微组织及回火硬度[J]. 金属热处理, 2016, 41(4): 30-34.
Ma Yongqing, Zhang Xiaojing, Liang Yufen. Microstructure and tempering hardness of Cr-W-Mo-V high alloy medium-upper carbon steel[J]. Heat Treatment of Metals, 2016, 41(4): 30-34.

[1]	Qi Xiaoliang, Li Yan, Ding Wei, Zhao Zengwu. Effect of original microstructure of medium manganese TRIP steel containing Al on microstructure and mechanical properties after intercritical annealing [J]. Heat Treatment of Metals, 2022, 47(4): 24-29.
[2]	Li Li, Zeng Yan, Wu Xiaochun. Heat treatment process optimization for 4Cr5Mo2VCo steel [J]. Heat Treatment of Metals, 2022, 47(4): 133-140.
[3]	Wang Fangjun, Wang Dongzhe, Wan Hong, Shi Yao, Shen Tao. Effects of heat treatment and cold deformation on linear expansion coefficient of constant expansion alloy 4J32C [J]. Heat Treatment of Metals, 2022, 47(4): 199-203.
[4]	Wang Shaozhuo, Meng Han, Wang Fen, Fan Haiwei, Li Yan, Tang Chao. Heat treatment for improving mechanical properties of hypoxic TC4-LC and remelted TC4 alloys [J]. Heat Treatment of Metals, 2022, 47(4): 204-207.
[5]	Su Yong, Wang Shuai, Wang Jixing, Yu Xingfu, Liu Hongxiu, Liu Jinling. Effect of compound chemical heat treatment on microstructure and hardness of G13Cr4Mo4Ni4V steel [J]. Heat Treatment of Metals, 2022, 47(4): 226-230.
[6]	Wang Jingyuan, Wu Songquan, Zhang Bohua, Xin Shewei, Yang Yi, Wang Hao, Huang Aijun. Effects of solution treatment and aging on microstructure and hardness of BT25y titanium alloy [J]. Heat Treatment of Metals, 2022, 47(3): 14-19.
[7]	Chen Liansheng, Fang Ning, Cao Zhongqian, Yang Zixuan, Li Hongbin, Pan Hongbo, Tian Yaqiang. Effect of intercritical warm-rolling reduction ratio on microstructure and properties of medium manganese steel treated by quenching and partitioning [J]. Heat Treatment of Metals, 2022, 47(3): 28-33.
[8]	Fan Yang, Yang Minghua, Chen Kaimin, Sun Bingyan. Effect of PWHT on microstructure and mechanical properties of electron beam welded joints of 31CrMoV9 steel [J]. Heat Treatment of Metals, 2022, 47(3): 57-60.
[9]	Chen Shanyong, Wang Kuaishe, Qiao Ke, Wang Wen. Effect of alkali heat treatment on corrosion resistance of friction stir processed AZ31 magnesium alloy [J]. Heat Treatment of Metals, 2022, 47(3): 61-66.
[10]	Fang Xiurong, Liu Liu, Xu Huihui, Gao Yang. Effect of pre-heat treatment before carburizing on distortion of gear shaft made of 17CrNiMo6 steel [J]. Heat Treatment of Metals, 2022, 47(3): 113-118.
[11]	Zhang Ying, Wang Haojun, Chen Suming, Hu Guang, Ouyang Delai, Cui Xia, Hu Shengshuang. Effect of heat treatment on microstructure and mechanical properties of laser solid forming TB18 titanium alloy [J]. Heat Treatment of Metals, 2022, 47(3): 124-129.
[12]	Hai Xianü, Yang Yang, Huang Taiwei, Fan Wangzhan, Gui Weimin, He Liangliang. Heat treatment properties of 8620H steel with refined graded hardenability [J]. Heat Treatment of Metals, 2022, 47(3): 155-158.
[13]	Long Liang, Hu Qixian, Luo Yun, Zheng Hongxiang, Wang Yujie. Optimization design of anti-distortion tooling for local heat treatment of large welded vessels [J]. Heat Treatment of Metals, 2022, 47(3): 234-238.
[14]	Cui Ding, Che Yongping. Distortion control method of parts with internal spline [J]. Heat Treatment of Metals, 2022, 47(3): 252-256.
[15]	Liu Tao, Wu Hongyan, Gao Xiuhua, Qin Dongyang, Du Linxiu. Effect of intercritical tempering temperature on microstructure and mechanical properties of Fe-4Mn-1.2Cr-0.3Cu-0.6Ni medium manganese steel [J]. Heat Treatment of Metals, 2022, 47(2): 91-98.