15-5PH不锈钢的热变形行为及热加工图

Hot deformation behavior and processing map of 15-5PH stainless steel

在Gleeble-3800热模拟试验机上对15-5PH钢进行高温热压缩试验,研究该材料在变形温度850-1180℃、应变速率0.001-10 s^-1、真应变量约为0.9条件下的热变形行为。采用双曲正弦模型建立了该材料的高温变形本构关系,依据动态材料模型建立并分析了其热加工图。结果表明：在热压缩过程中,峰值应力随变形温度的升高而减小,随应变速率的升高而增大,当变形速率较低时,材料在变形温度范围内均发生了动态再结晶。15-5PH钢的热变形激活能为228.41 k J/mol。从热加工图中获得了该材料最佳热加工参数范围是：变形温度1000-1150℃、应变速率0.001-0.1 s^-1。

Hot deformation behavior of 15-5 PH stainless steel was studied by a Gleeble 3800 simulator at 850-1180 ℃ with the strain rate of0. 001-10 s^-1 and the true strain of 0. 9. The hot deformation constitutive relationship was established by using the hyperbolic-sine mathematics model. Processing maps were also established based on the dynamic materials model. The results show that the peak stress decreases with the increase of deformation temperature and increases with the increase of strain rate. When the strain rate is low,the dynamic recrystallization of the steel occurs in the range of deformation temperature. The hot deformation activation energy Q of the steel is 228. 41 k J/mol.It can be seen from the processing maps that the optimal deformation processing parameters are the deformation temperatures ranging from1000 ℃ to 1150 ℃ and the strain rates ranging from 0. 001 to 0. 1 s^-1.