【摘要】 采用Gleelbe-3500热力模拟试验机对2507双相不锈钢在900～1 150℃,以0.01～10 s^-1的应变速率进行了单向热压缩试验，以研究热变形参数对其热加工行为的影响。根据热压缩变形时的真应力-真应变曲线获得双相不锈钢基于动态材料模型理论的热加工图，并通过金相检验对热加工图进行验证。结果表明：2507双相不锈钢的真应力-真应变曲线有两个特征，即高温或应变速率较大时的动态回复和低温或应变速率较小时的动态再结晶。根据热变形方程计算得到该双相不锈钢的热变形激活能Q为473.01 kJ/mol,并构建了峰值应力本构方程。结合不同变形条件下的应力-应变曲线和显微组织，建立了2507双相不锈钢的热加工图，并确定了其最佳的热加工工艺区间为变形温度950～1 100℃,应变速率0.01～0.85 s^-1,该区域的功率耗散系数均大于0.3,发生了明显的奥氏体动态再结晶。更多还原

【Abstract】 Uniaxial hot compression tests for the 2507 duplex stainless steel（DSS） were carried out by a Gleeble-3500 thermal simulator at temperatures ranging from 900 to 1 150 ℃ and at strain rates ranging from 0.01 to 10 s^-1, to research the effect of the thermal deformation parameters on its hot working behavior. The hot working map for the duplex stainless steel based on a dynamic materials model（DMM） theory was derived from the true strain-true stress curve during hot compression deformation, and verified by metallographic examination. The results showed that the true strain-true stress curves for the 2507 duplex stainless steel had two characteristics, among which were: dynamic recovery under the condition of high temperature or larger strain rate, and dynamic recrystallization（DRX） under the condition of low temperature or smaller strain rate. The thermal deformation activation energy（Q） of the duplex stainless steel calculated in accordance to the hot deformation equation was 473.01 kJ/mol, and a constitutive equation for the peak flow stress was established. In combination with the true strain-true stress curve and microstructure under different deformation conditions, the hot working map for the 2507 duplex stainless steel was constructed, and the optimum hot working region was determined as follows: deformation temperatures ranging from 950 to 1 100 ℃ and strain rate ranging from 0.01 to 0.85 s^-1, power dissipation coefficient being more than 0.3, DRX of austenite being obvious in this region.更多还原