409L铁素体不锈钢热变形行为

采用热/力模拟实验方法研究了409L铁素体不锈钢(409LFSS)在950～1150℃、应变速率为0.05～2.5 s-1条件下的热变形及组织变化,讨论了热变形参数对流变应力和显微组织的影响.结果表明,409L铁素体不锈钢的表观应力指数及热变形表观激活能分别为4.45、262 kJ/mol;其热变形方程为ε=5.347×1011[sinh(α·σp)]4.45exp(-262000/RT);该钢的铁素体软化机制与Z参数有关,且随着Z值从2.09×108增加到3.92×1011,热变形峰值应力相应从13.73 MPa增加到65.08 MPa.

Hot deformation behavior of 409L ferritic stainless steel

The hot deformation behavior and microstructure evolution of 409L ferritic stainless steel (409LFSS) were investigated at 1223-1423 K and strain rate at 0.05-2.5 s-1 using a thermo-mechanical simulator.The effects of temperature and strain rate on flow behavior and microstructure of 409L ferritic stainless steel at reduction ratio of 50% were analyzed.Results indicate that the apparent stress exponent and the apparent activation energy of the steel are 4.45 and 262 k J/mol,respectively.The hot deformation equation of 409LFSS,s= 5.347×1011[sinh(α·σp)]4.45 exp(-262000/RT],is obtained based on experiments.There is a relationship between the softening mechanism of the steel and Zener-Hollomon parameter(abbreviated Z).As the Z value increases from 2.09×108 to 3.92×1011,the hot deformation peak stress correspondingly increases from 13.73 to 65.08 MPa.