冲击加载作用下铁和镍的高应变率变形

采用飞片碰撞试验，研究了纯铁和纯镍的动态变形机制及其特点。结果发现：位错的生成率是有限的，最大仅是４．７８×１０１８ｃｍ－２·Ｓ－１。对应的最大应变率是８．５×１０５ｓ－１，位错的最大速度是１８．９ｃｍｓ－１。在最大冲击波压力下，材料的最大剪切应力是剪切模量Ｇ的１／２６。剪应力、位错速度和位错的生成与冲击波压力的关系是符合常规变形机制的。在实验所用的压力范围，位错不会均匀生核和以超声速移动。

HIGH STRAIN RATE DEFORMATION OF Fe AND Ni BY SHOCK LOADING

The dynamic deformation mechanism of pure iron and nical has been studied dy flat plate impact.It is found that the crder of 4.78×1018cm-2·s-1 of the finite dislocation generation rates result in a maximum Plastic strain rate on the order of 8.5×105·s-1 and a maximum dislocation velocity of 18.9cm·s-1.The maximum shear stress imposed on the material is estimated to be G/26 at maximum pulse pressure.The shear stresses,dislocation velocities and production of dislocation as a function of pressure are found to be consistent with conventional deformation.The dislocation can t be homogeneous nucleation or supersonic velceites.