Cause analysis of magnetic particle indication on 42CrMo steel crankshaft neck

doi:10.13251/j.issn.0254-6051.2020.04.047

Abstract

Abstract: The hair-line magnetic particle indication was detected by magnetic particle testing at the neck part of 42CrMo steel crankshaft. The microstructure just below the magnetic particle indication was studied by OM,SEM and EDS. The results show that the microstructure is considerably uneven,and significant segregation bands are found with a width of about 20-50 μm and enriched with the C, Mn, S, Al and Cr elements. In addition, individual MnS inclusion is also detected. The segregation bands paralleling with the axis of columnar 42CrMo steel are rotated during die forging process, especially at the neck part of 42CrMo steel crankshaft with severe plastic distortion.The macro-segregation is inherited to the final crankshaft product. The heterogeneous compositional distribution leads to the difference of magnetic permeability and thus the appearance of magnetic particle indication. The forging process and the following quenching-tempering as well as surface induction quenching treatment can mitigate to some extent but cannot totally eliminate the segregation.

Key words: 42CrMo steel, crankshaft, magnetic particle testing, segregation

CLC Number:

Huang Bin, Lin Shengyao, Mao Xiaofeng, Li Liangqun, Zheng Qifeng, Gu Jianfeng, Liu Qingdong. Cause analysis of magnetic particle indication on 42CrMo steel crankshaft neck[J]. Heat Treatment of Metals, 2020, 45(4): 224-228.

References

[1]张文, 朱百智, 黄振建, 等. 淬火介质对42CrMo钢棒淬火组织及硬度影响的数值模拟及试验验证[J]. 金属热处理, 2020, 45(1): 56-60.
Zhang Wen, Zhu Baizhi, Huang Zhenjian, et al. Numerical simulation and experimental verification of effect of quenching medium on quenching microstructure and hardness of 42CrMo steel rod[J]. Heat Treatment of Metals, 2020, 45(1): 56-60.
[2]刘杰, 李萌蘖, 李绍宏, 等. 42CrMo钢船用曲拐加热和淬火过程数值模拟[J]. 金属热处理, 2019, 44(11): 188-195.
Liu Jie, Li Mengnie, Li Shaohong, et al. Numerical simulation of heating and quenching process of 42CrMo steel crankshaft[J]. Heat Treatment of Metals, 2019, 44(11): 188-195.
[3]周恩明. 42CrMo钢制螺栓断裂失效分析[J]. 金属热处理, 2019, 44(11): 241-244.
Zhou Enming. Fracture failure analysis of 42CrMo steel bolt[J]. Heat Treatment of Metals, 2019, 44(11): 241-244.
[4]刘洪波, 王秀兰, 李艾. 42CrMo汽车曲轴失效分析[J]. 黑龙江冶金, 2016, 36(5): 7-9.
Liu Hongbo, Wang Xiulan, Li Ai. Failure analysis of 42CrMo automotive crankshaft[J]. Heilongjiang Metallurgy, 2016, 36(5): 7-9.
[5]刘敬平, 王翠芳, 卢杉. 42CrMo钢半轴的断裂失效分析[J]. 热加工工艺, 2017, 46(16): 251-253.
Liu Jingping, Wang Cuifang, Lu Shan. Fracture failure analysis of 42CrMo steel half shaft[J]. Hot Working Technology, 2017, 46(16): 251-253.
[6]胡艳春, 傅建斌. 42CrMo电渣重熔铸造曲轴断裂分析[J]. 柴油机, 2017, 39(2): 53-55.
[7]印小松, 董旭刚, 周兵, 等. 42CrMo曲轴裂纹原因分析及改进措施[J]. 金属加工(热加工), 2016(11): 78-80.
[8]李小泉, 吕云飞, 赵海新, 等. 42CrMo钢曲轴断裂失效分析[J]. 热加工工艺, 2014, 43(2): 217-218.
Li Xiaoquan, Lü Yunfei, Zhao Haixin, et al. Failure analysis of 42CrMo steel crankshaft[J]. Hot Working Technology, 2014, 43(2): 217-218.
[9]蔡铁庄, 王文. 42CrMo曲轴镦锻开裂原因分析[J]. 大型铸锻件 2009(4): 24-26.
Cai Tiezhuang, Wang Wen. Analyzing the cause of 42CrMo crankshaft cracking by upset forged[J]. Heavy Casting and Forging, 2009(4): 24-26.
[10]赵雯, 岳晓丽, 陈慧敏, 等. 42CrMo钢调质处理后力学性能的预测[J]. 金属热处理, 2017, 42(7): 158-162.
Zhao Wen, Yue Xiaoli, Chen Huimin, et al. Prediction of mechanical properties of 42CrMo steel after quenching and tempering treatment[J]. Heat Treatment of Metals, 2017, 42(7): 158-162.
[11]朱美玲. 锻钢曲轴磁痕形成机理研究[D]. 洛阳: 河南科技大学, 2015.
Zhu Meiling. Research on the formation mechanism of forged steel crankshaft magnetic marks[D]. Luoyang: Henan University of Science and Technology, 2015.

[1]	Yang Jing, Dong Nan, Jiang Zhouhua, Han Peide. Segregation and influence of alloying elements at fcc-Fe/NbX (X=C, N) interface [J]. Heat Treatment of Metals, 2022, 47(4): 57-62.
[2]	Yang Jie, Wang Xi, Zhou Jie, Wu Jianxiang, Qu Zhiyuan, Dai Heping, Peng Haijun. Formation mechanism of quenching cracks in branch-shaped structure of steering knuckle forgings [J]. Heat Treatment of Metals, 2022, 47(4): 263-267.
[3]	Zhang Ning, Gao Xing, Wang Zhilin, Jiang Bo, Liu Yazheng. Analysis of abnormal microstructure and properties of 18CrNiMo7-6 steel gear [J]. Heat Treatment of Metals, 2022, 47(4): 268-273.
[4]	Wu Hui, Lin Shengyao, Li Xinkai, Gong Yuhui, Wei Deqiang. Effect of induction hardening on microstructure and properties of 42CrMo steel crankshaft connecting rod journal [J]. Heat Treatment of Metals, 2022, 47(2): 119-124.
[5]	Wu Yingfei, Sun Zhonghua, Wang Yufei, Wang Chengming, Zhang Yunfei, Peng Huifen. Effect of homogenizing on microstructure and properties of Invar alloy ingot [J]. Heat Treatment of Metals, 2022, 47(2): 130-136.
[6]	Wang Zili, Chen Rongfa, Zheng Zhiwei, He Yulong, Shi Minjie, Wang Kai, Zhou Xiaojin. Microstructure and wear resistance of oxynitriding layer on piston rod surface of 42CrMo steel [J]. Heat Treatment of Metals, 2021, 46(8): 225-229.
[7]	Ji Guoqiang, Ge Guiming, Yu Lijuan, Zhong Jizhi. Analysis on cracking of 50CrV4 steel washer [J]. Heat Treatment of Metals, 2021, 46(7): 254-257.
[8]	Zhao Peilin, Liu Chao, Wu Huiliang, Zheng Li. Effect of normalizing temperature on microstructure and low temperature toughness of 355 MPa heavy section steel for marine engineering [J]. Heat Treatment of Metals, 2021, 46(6): 102-106.
[9]	Yan Yong, Bu Hengyong, Li Mengnie, Zheng Shanju. Kinetics of austenite grain growth of S34MnV steel [J]. Heat Treatment of Metals, 2021, 46(6): 153-159.
[10]	Ji Shuang, Li Huilin, Zhao Xiujuan, Zhang Yunfei, Zhao Yingli, Chen Wen, Shi Yulong, Xing Chengliang. Forging cracking cause analysis of Ni-based corrosion-resistant alloy Hastelloy C-276 [J]. Heat Treatment of Metals, 2021, 46(6): 240-244.
[11]	Jiao Li, Shang Haikun, He Jianfeng, Zhao Yingjun, Zhang Weimin, Li Weimin, Zhou Lanmei. Fracture failure analysis of 42CrMo steel high strength bolts for diesel engine [J]. Heat Treatment of Metals, 2021, 46(6): 245-249.
[12]	Peng Ze, Li Mengnie, Bu Hengyong, Li Qi. Evolution of austenite grain size of 42CrMo steel during heating [J]. Heat Treatment of Metals, 2021, 46(5): 25-31.
[13]	Yan Youzeng, Zhang Hao, Cao Qi, Meng Gaoqiang, Xia Guofeng, Xu Shuang. Causes analysis of quenching cracking of inner hole of first class planet carrier [J]. Heat Treatment of Metals, 2021, 46(4): 236-238.
[14]	Jiang Shichuan, Zhang Jian, Han Fu. As-cast microstructure characteristics and homogenization treatment of GH4169 alloy [J]. Heat Treatment of Metals, 2021, 46(2): 109-117.
[15]	Meng Xuan, Yue Jiahong, Kong Lingfei, Yang Yang, Jia Peng. Effect of nitriding temperature on post-oxidating infiltrated layer of 42CrMo steel part surface [J]. Heat Treatment of Metals, 2021, 46(2): 182-184.