高应变率拉伸加载下无氧铜的本构模型

摘要: 为了研究材料在高应变率拉伸加载下的动态响应,利用新型爆炸膨胀环实验技术开展了无氧铜试样环的拉伸加载实验,采用激光干涉测试技术获得了试样环拉伸变形过程的径向速度历史。数值计算发现经典JC模型不能较好地描述无氧铜试样环的膨胀过程,于是对JC模型进行了修改:增加了应变的指数硬化项来描述拉伸变形的累积效应;增加了应变率的线性项描述拉伸加载时的应变率效应;利用实验数据拟合了修改后的RJC模型参数,最终较好描述了无氧铜试样环的膨胀变形过程。
- 固体力学 /
- 无氧铜 /
- 高应变率 /
- 本构模型 /
- 拉伸
Abstract: Tostudythedynamicresponseofmaterialsundertensileloadingathighstrainrates,tensile- loadingexperimentswereconductedonoxygen-freecopperexpandingringsbyapplyinganewexpandingringexperimenttechnique. Theradialvelocitiesofthecopperexpandingringsduringtensile deformationweremeasuredbyVISARorFDI.TheempiricalJohnson-Cook(JC)constitutivemodel wasusedtosimulatetheexpandingprocessofoxygen-freecopperrings.Thecalculatedresultsareobviouslyhigherthantheexperimentalones. SoaregulativeJCmodelfortensiledeformation(RJC)was proposedtoimprovetheempiricalJCconstitutivemodel.IntheRJC model,anewindexterm of strainhardingwasaddedtodescribetheaccumulatedeffectinthedynamictensiledeformationprocess aswellasanewlineartermofstrainratetodescribethestrain-rateeffectundertensileloading.And theparametersoftheRJCmodelwereobtainedbyfittingtotheexperimentdata.ThefurthernumericalresultsshowthattheRJCmodelcandescribetheexpandingdeformationprocessoftheoxygen- freecopperrings.
- solidmechanics /
- oxygen-freecopper /
- highstrain-rate /
- constitutivemodel /
- tension