不锈钢材料的动态力学性能及本构模型

Dynamic mechanical behavior and constitutive model of stainless steel

利用带有温度调控系统的SHPB实验装置测定了0Cr17Mn5Ni4Mo3Al不锈钢在3种应变率(3001、000、2 700 s-1)、4种环境温度(25、300、500和700℃)下的应力应变关系;在液压伺服材料试验机(MTS)上进行了3种温度下的准静态(0.000 5 s-1)压缩实验。实验结果表明:该不锈钢有明显的应变率强化效应和温度软化效应,并且随着环境温度的升高,应变率强化效应减弱。对Johnson-Cook模型进行了修正,考虑了冲击过程中绝热温升引起的软化效应。修正后的Johnson-Cook模型与实验结果吻合较好。

Stress-strain curves of 0Cr17MnSNi4Mo3Al, at three Strain rates of 300,1 000,2 700 s^-1 and four temperatures of 25,300,500,700 ℃ were experimentally obtained by using the split Hopkinson pressure bar equipped with a temperature controller. And the quasi-static experiment （0. 000 5 s^-1） was done in the material test system at three temperatures of 25,300,500 ℃. Experimental results show that the flow stress decreases with temperature but increases with strain and strain rate. The traditional Johnson-Cook model was modified considering the thermal softening caused by the impact adiabatic process. The modified Johnson-Cook model is in good agreement with the experimental results.