Mechanical model for yield strength of nanocrystalline materials under high strain rate loading
作者单位：School of Mechanical EngineeringNanj ing University of Technology School of Mechanical EngineeringNanjing University of Technology School of Materials Science and EngineeringNanjing University of Technology
会议名称：《The 9th National Conference on Rheology》
会议日期：2008年
学科分类：07[理学] 070205[理学-凝聚态物理] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学]
基 金：Project(10502025) supported by the National Natural Science Foundation of China Project(lOl005) supported by Fok Ying Tong Education Foundation Project(BK2007528) supported by the Natural Science Foundation of Jiangsu Province,China
关 键 词：nanocrystalline materials deformation mechanism modeling yield strength high strain rate
摘 要：正To understand the high strain rate deformation mechanism and determine the grain size,strain rate and porosity dependent yield strength of nanocrystalline materials,a new mechanical model based on the deformation mechanism of nanocrystalline materials under high strain rate loading was *** a first step of the research,the yield behavior of the nanocrystalline materials under high strain rate loading was mainly concerned in the model and uniform deformation was assumed for simplification. Nanocrystalline materials were treated as composites consisting of grain interior phase and grain boundary phase,and grain interior and grain boundary deformation mechanisms under high strain rate loading were analyzed,then Voigt model was applied to coupling grain boundary constitutive relation with mechanical model for grain interior phase to describe the overall yield mechanical behavior of nanocrystalline *** predictions by the developed model on the yield strength of nanocrysatlline materials at high strain rates show good agreements with various experimental *** discussion was presented for calculation results and relative experimental observations.