In this paper, the carburizing-quenching process of carbon steel is analyzed with computer simulation which is based on the metallo-thermo-mechanical theory and finite element analysis coupled temperature, phase trans...In this paper, the carburizing-quenching process of carbon steel is analyzed with computer simulation which is based on the metallo-thermo-mechanical theory and finite element analysis coupled temperature, phase transformation and stress/strain fields. The residual stresses and distortion of a steel cylinder during carburizing quenching process were predicted and compared with experimental data. From the prediction results, improvement of hardness and strength of the cylinder component in carburizing-quenching process was verified.展开更多
The considerable heat treatment induced runout value in the end face of the automobile main reducer gear is always dimensionally out of tolerance.It directly affects the dimensional accuracy,the grade of carburized an...The considerable heat treatment induced runout value in the end face of the automobile main reducer gear is always dimensionally out of tolerance.It directly affects the dimensional accuracy,the grade of carburized and hardened gears,and the post-quenching manufacturing costs.In this study,three dimensional numerical models were developed to simulate the carburizing-quenching process of gear based on the multi-field coupling theory using DEFORM software.The results indicated that the ununiform cooling rate of the gear caused by the asymmetry of the web structure would result in the ununiform distribution of martensite,leading to the large runout value at the end face of the gear.Therefore,a novel method was proposed to minimize the heat treatment induced runout value.It was found that the heat treatment induced runout value could be effectively controlled by the addition of a compensation ring and the support of a rod structure.Further experiments showed that the average runout value of the gear end face before and after the proposed heat treatment method were about 0.023 mm and 0.059 mm respectively,which was in good agreement with the simulated results.The novel approach proposed in this study led to a reduction of the gear runout value by 70.0%‒76.9%compared to that of the original heat treatment process,which may serve as a practical and economical way to predict and minimize the heat treatment induced distortion in drive gear.展开更多
文摘In this paper, the carburizing-quenching process of carbon steel is analyzed with computer simulation which is based on the metallo-thermo-mechanical theory and finite element analysis coupled temperature, phase transformation and stress/strain fields. The residual stresses and distortion of a steel cylinder during carburizing quenching process were predicted and compared with experimental data. From the prediction results, improvement of hardness and strength of the cylinder component in carburizing-quenching process was verified.
基金National Key R&D Program of China(Grant No.2019YFB2004700)State Key Laboratory of High Performance Complex Manufacturing of China(Grant No.ZZYJKT2019-08)China Postdoctoral International Exchange Program(Grant No.140050004).
文摘The considerable heat treatment induced runout value in the end face of the automobile main reducer gear is always dimensionally out of tolerance.It directly affects the dimensional accuracy,the grade of carburized and hardened gears,and the post-quenching manufacturing costs.In this study,three dimensional numerical models were developed to simulate the carburizing-quenching process of gear based on the multi-field coupling theory using DEFORM software.The results indicated that the ununiform cooling rate of the gear caused by the asymmetry of the web structure would result in the ununiform distribution of martensite,leading to the large runout value at the end face of the gear.Therefore,a novel method was proposed to minimize the heat treatment induced runout value.It was found that the heat treatment induced runout value could be effectively controlled by the addition of a compensation ring and the support of a rod structure.Further experiments showed that the average runout value of the gear end face before and after the proposed heat treatment method were about 0.023 mm and 0.059 mm respectively,which was in good agreement with the simulated results.The novel approach proposed in this study led to a reduction of the gear runout value by 70.0%‒76.9%compared to that of the original heat treatment process,which may serve as a practical and economical way to predict and minimize the heat treatment induced distortion in drive gear.
