Microstructure and properties of new hot work die steel for hot stamping

doi:10.13251/j.issn.0254-6051.2020.09.033

Abstract

Abstract: Microstructure,thermo stability,thermal physical property and high temperature wear resistance of a new die steel for hot stamping of high strength steel were investigated by means of scanning electron microscope (SEM),transmission electron microscope (TEM),LF457 type laser flash thermal analyzer,DSC404 type differential scanning calorimeter and UMT-3 high temperature wear test system.The results show that the new hot stamping die steel has excellent resistance to tempering,thermo stability,thermal conductivity and high temperature wear resistance and better adapt to the working condition of high strength steel hot stamping process.There are mainly Mo₂C and VC type carbides in the steel,these carbides ensure the steel with high resistance to tempering and thermo stability.The steel has high thermal conductivity,which is 1.4 times of H13 steel at room temperature.The low Si,Mn,Cr and high Mo alloying can be the reason for the high thermal conductivity of the steel.The new die steel has better high temperature wear resistance than that of H13 steel,especially when temperature is above 600 ℃,which can decrease the repair frequency and improve service life of the hot stamping die.

Key words: hot stamping die steel, thermal stability, thermal conductivity, high temperature wear resistance

CLC Number:

TG142.7

Li Shuang, Gao Yunfei, Wang Chen, Wang Zhen, Shi Yongliang, Wu Xiaochun. Microstructure and properties of new hot work die steel for hot stamping[J]. Heat Treatment of Metals, 2020, 45(9): 178-184.

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