火灾爆炸作用下921A钢力学性能及本构关系

采用万能试验机和霍普金森压杆(SHPB)系统,对火灾爆炸下921A钢高温力学性能及动态力学性能进行研究。基于试验数据,分别拟合Johnson-Cook本构模型、Cowper-Symonds本构模型,修正Cowper-Symonds模型应变硬化项,并通过试验验证了有效性。参考Johnson-Cook本构模型温度项耦合方法,建立综合考虑温度软化效应和应变率强化效应的921A钢本构模型。

Mechanical behavior and constitutive relation of steel 921A under effects of blast and fire

In this paper, we studied the mechanical properties at elevated temperature and dynamic mechanical properties of ship-built steel 921A under fire and blast using universal testing machine and Split Hopkinson Pressure Bar (SHPB) system. Based on the dynamic compression test data, we fitted the Cowper-Symonds constitutive model and Johnson-Cook constitutive model, modified the strain hardening term of the Cowper-Symonds model, then verified their validity by the experiment. Referring to the method of coupling of temperature term in Johnson-Cook constitutive model, we proposed a 921A steel constitutive model considering the effect of temperature softening and strain rate strengthening.