喷射成形高合金工具钢的流变应力本构方程

Flow Stress Constitutive Equation of Spray Forming High-alloyed Tool Steel

采用喷射成形工艺制备了HGSF01高合金工具钢,在Gleeble2000热模拟试验机上进行等温热压缩试验,在变形速率为0.05～20 s-1和变形温度为900～1150℃条件下对喷射成形HGSF01高合金工具钢进行实验研究。结果表明:喷射成形HGSF01高合金工具钢热压缩变形流变应力受变形温度和应变速率的影响强烈,真应力-应变曲线呈典型的动态回复再结晶特征。可以用Zener-Hollomon参数的双曲正弦函数形式本构方程来描述喷射成形HGSF01高合金工具钢的流变应力行为,其形变激活能(Q)为435.446 kJ/mol。

The HGSF01 high-alloyed tool steel was manufactured by spray forming technology. The hot compression tests of the steel were performed on Gleeble 2000 machine at 900-1150℃ and strain rates of 0.05 20 s^-1. The results show that the flow stress of spray forming HGSF01 high-alloyed tool steel depends strongly on the deformation temperature and strain rates, and the true stress-strain curves of the steel show typical dynamic recover and dynamic recrystallization features. The flow stress behaviors of the steel can be represented by Zener-Hollomon parameters in the hyperbolic-sine-type constitutive equation, and the deformation activation energy （Q） of the steel is 435.446 kJ/tool.