Dynamic compressive mechanical behavior of a stainless steel material was studied at elevated temperatures and high strain ratesby using split Hopkinson pressure bar (SHPB) , which was installed with heating and synchro assembly system. The tests were carried out at loading rates ranging from 1100 to 16000 s-1 and temperatures from 20 to 800℃. The strain rate and temperature sensitivities of flow stress are analyzed. The intrinsic mechanism is discussed according to the thermally activated dislocation motion theory. The results show that the material has evident heat softening effect and strain rate hardening effect. And both the strain rate and temperature sensitivities of the material are increased at higher temperatures.%利用带有加热装置和同步组装系统的高温Hopkinson压杆系统对某不锈钢材料在温度20 ～ 800℃时,应变率103 ～ 104s-1下的动态压缩力学性能进行了测试,得到了材料在不同温度和应变率耦合作用下的真实应力-应变曲线.对比准静态结果,考察了材料流动应力的温度和应变率敏感性,并根据热激活位错运动理论对其内在机理进行了解释和探讨.试验表明,材料具有显著的热软化和应变率强化效应；且高温时,材料的温度敏感性、应变率敏感性均显著增加.
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