单晶体单滑移的变形和稳定性分析

Deformation and stability analysis of single crystal for single slip

从细观的晶体塑性力学出发,研究了在单向拉伸下的单晶体单滑移的变形和稳定性问题,定量给出了滑移面的方位和滑移方向随应变ε的变化规律。定义了失稳参数S,把用正应力和正应变表示的塑性变形稳定性条件,变换成适合于细观塑性力学应用的用切应力和切应变表示的稳定性条件。结果表明:材料滑移面向拉伸方向偏转并趋于一致,即应变ε增加时,滑移方向方位角λ在减小,滑移面方位角χ在增大;失稳参数S随着应变ε的增加而减少。

Deformation and stability of single crystal for single slip under simple tension were studied based on the point of meso-plastic mechanics of crystal.The change rules of the direction of slip surface and direction of slip along with the strain ε were presented quantitatively.The instability parameter S was defined and the condition of stability of plastic deformation represented by normal stress and normal strain was changed to shear stress and shears strain fitted for applying meso-plastic mechanics.The results show that the slip planes deflect to the direction of tension and trend to accordant,the larger strain ε is,the smaller λ（angle of slip direction） is and the larger χ（angle of slip surface direction）is;the larger strain ε is,the smaller the instability parameter S is.