HQ80C 和 HQ100钢剪切屈服强度对温度和应变速率的敏感性

THE SENSITIVITY OF TEMPERATURE AND STRAIN RATE ON THE SHEAR YIELD STRESS OF HQ80C AND HQ100 STEELS

本文对 HQ80C 和 HQ100 钢在不同温度、不同应变速率下的屈服强度进行了研究。发现在不同温度的τ_s-lg(?)关系曲线上,Rosenfield 定义的Ⅰ区和Ⅱ区同属于位错运动的热激活机制。将Dorn-Rajnak 理论用于本研究,证明本文所研究的两种材料的形变对温度和应变速率敏感的机理是位错运动的 Peierls 机制中的 P-N 力对其敏感所致。

The shear yield stresses of HQ80C and HQ100 steel at different tempertures andstrain rates were measured.Following Rosenfield and Hahn,τ_s-L_gγ curve can be refered toas region Ⅰ and Ⅱ.It was found that the deformation mechanisms in region Ⅰ and Ⅱ are boththermal activiation mechanisms.By applying the theory of Dorn-Rajnak in this study,the sen-sitivity of macro yield strength to temperature and strain rate of the materials studied is causedby the sensitivity of P-N force to temperature and strain rate.