应力空间和应变空间的后继屈服面演化

 屈服面的位置和形状直接影响材料塑性应变的确定。考虑滑移是晶体的主要塑性变形机制，介绍了晶体塑性理论的推广--滑移构元模型，研究了应力空间和应变空间的后继屈服面演化。给出了确定应力空间和应变空间屈服面的数值计算方法，提出一种考虑屈服面畸变变形的混合硬化假设，可以描述应力空间和应变空间后继屈服面的移动和畸变变形。通过计算1100-O 铝在纯扭转和拉扭组合加载下（σ₁₁ -σ₁₂）空间和（ε₁₁ -γ₁₂）的后继屈服面演化，与已有实验结果吻合。研究结果表明，无论是在应力空间还是应变空间，后继屈服面“前凸后扁”的变形特征可基于滑移构元的潜在硬化和包氏效应来描述。

Research on the Evolution of Subsequent Yield Surfaces in Stress Space and Strain Space

The shape and position of yield surface have a direct influence on the determination of plastic deformation of materials. Considering that slip is the main plastic deformation mechanism, the extension of single crystal plasticity called slip-component model is introduced, and the evolution of subsequent yield surfaces in stress space and strain space is investigated. The method to determine the yield surfaces in stress space and strain space is proposed. A combined kinematic-distortional hardening model is developed to describe the translation and distortion of subsequent yield surfaces in stress space and strain space. Numerical simulations of the evolution of subsequent yield surfaces in (σ₁₁ -σ₁₂) stress space and (ε₁₁ -γ₁₂) strain space are performed under pure torsion and combined tension- torsion loading for aluminum 1100- O. The results show that the agreement between the predictions and experiments is quite satisfactory. The work demonstrated that whether in stress space or strain space, based on the latent hardening and Bauschinger effect of the slip component, the subsequent yield surface can be described that the forward part inflates and the rear part deflates so that the subsequent yield surface has a sharp front and a blunt rear.