Transactions of Materials and Heat Treatment

Title：Producing hot stamping parts with variable strengths by a new die and study on mechanical properties of stamping parts

Authors： Bao Li Gu Quan Cai YouJie Wu Zhidong Liu Meng Liu Shang

Unit： Qiqihar University Liaoning Institute of Science and Technology

KeyWords： new die hot stamping stamping parts with variable strengths mechanical properties FE simulation

ClassificationCode：TG142.33

year,vol(issue):pagenumber：2017,42(9):123-128

Abstract：

A new type of hot stamping partition die was designed to form parts with variable strengths by induction heating, and the thermal fluid solid coupling theory analysis was carried out. Then, the finite element model with thermal mechanical coupling was established, and the temperature and Vickers hardness distributions of sheet metal in hot stamping were obtained. The simulation results show that the cooling rate of heating die is 13.6 ℃·s-1 when the temperature of induction heating end of the die raises to 400 ℃, so the microstructure and Vickers hardness of sheet metal at different temperatures are determined by different cooling rates. Furthermore, the hot stamping experiments are carried out by the die, and the microstructure and Vickers hardness at different temperatures regions are examined. The results show that the new die can form parts with high temperature zone （low strength）, and the bainite microstructure of stamping parts is transformed from the high temperature zone, the martensite as well as bainite and ferrite multiphase mixed microstructures are transformed from the transition zone respectively, the lath-shape martensite is transformed from low temperature region. The new hot stamping die can obtain stamping parts with variable strengths and provides the basis for obtaining stamping parts with variable strength and the optimization of process parameters.

Funds：

黑龙江省教育厅基本业务专项理工青年骨干项目（135109310）

包丽（1984-），女，博士，副教授 E-mail：bl19841222@163.com

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