淬硬45钢在高温、高应变率下的动态力学性能及本构关系

摘要: 在20℃~800℃的温度范围和10-3~104s-1的应变率范围内,采用电子万能试验机和分离式霍普金森压杆,对淬硬45钢(45HRC)分别进行准静态实验和动态压缩力学性能实验,得到应力应变曲线。结果表明:淬硬45钢的流动应力对应变率敏感性一般,但表现出较强的温度敏感性,随着应变率的增大而增大, 随着温度的升高而降低。采用以高斯函数表示温度效应的改进Johnson-Cook本构方程拟合了淬硬45钢在高应变率和高温条件下的本构关系,拟合曲线与实验数据吻合较好。
- 固体力学|动态力学性能|高应变率|淬硬45钢|本构关系 /
- 高温
Abstract: Toexplorethedynamicmechanicalpropertiesofhardenedsteel(45HRC),quasi-staticand dynamiccompressionexperimentswereperformedinthetemperaturerangefrom20℃to800℃and thestrainraterangefrom10-3s-1to104s-1 byusinganelectronicuniversaltestingmachineanda splitHopkinsonpressurebarsystem,respectively.Andthestress-straincurveswereexperimentally obtained.Theresultsindicatetheflowstressofhardened45steelisnotsensitivetostrainrate,but sensitivetotemperature.Theflowstressincreaseswiththeincreaseofstrainrateanddecreaseswith theincreaseoftemperature.Theconstitutiverelationshipofhardenedsteel(45HRC)underhightemperatureandhighstrainratewasfittedbytheimprovedJohnson- Cookconstitutiverelationshipin whichtheGaussianfunctionwasusedtodescribethetemperatureeffect.Thefittedcurveisingoodagreementwiththeexperimentaldata.
- solidmechanics /
- dynamicmechanicalproperties