贝氏体塑料模具钢SDP1热压缩流动应力及晶粒度的研究

Study on Flow Stress and Grain Size of Bainitic Plastic Die Steel SDP1 during Hot Compression

为了掌握贝氏体塑料模具钢SDP1的热变形规律,采用Gleeble-3500热模拟实验机进行了850、1000、1150℃变形温度和0.0015、0.015、0.15 s^-1变形速率下的热压缩实验,分析了不同参数下钢的流动应力和晶粒尺寸变化规律。结果表明:变形温度在晶粒尺寸控制中起关键作用,在0.0015 s^-1和1000℃条件下得到最小平均晶粒直径。建立了SDP1钢热压缩流动应力本构方程,其热变形激活能为283.5 kJ/mol。

In order to understand the thermal deformation law of bainite plastic die steel SDP1,the hot compress test was conducted by using the Gleeble-3500 thermal simulation tester at the temperatures of 850,1000,1150℃and the strain rates of0.0015,0.015,0.15 s^-1,and the flow stress and grain size variation of the steel under different parameters were analyzed.The results show that the deformation temperature plays a key role in the controlling of grain size,and minimum average grain diameter is obtained under conditions of 0.0015 s^-1 and 1000℃.The constitutive equation for the hot compression flow stress of SDP1 steel was established,and the hot deformation activation energy of SDP1 steel is 283.5 kJ/mol.