Microscopic Approach of Plastic Deformation of Particles and Coupled Analysis with Macroscopic Approach

提出了一种用有限元方法模拟粉末颗粒在压制过程中微观致密化行为的方法。该方法通过检测压实过程中粉末颗粒之间的接触，用有限元方法计算粉末颗粒在接触过程中的塑性变形。假定有限元是多孔金属，其平均相对密度由单元内部的粉末和气孔的体积计算得出。将单元分为传统有限元方法中使用的三角形单元和四边形单元，以及用于简单压缩的线性单元。比较了平面应变压实过程中粉末颗粒塑性变形刚度与铝棒模型试验的精度。

An approach for simulating microscopic densification behavior of powder particles in compaction using a finite element method is proposed. In this method, the contacts between powder particles during the compaction are detected, and plastic deformation of the particles is calculated by the finite element method in contact. It is assumed that the finite elements are porous metals having an average relative density calculated from the volumes of the powder and pore inside the element. The elements are classified into the triangular and quadrilateral ones used in the conventional finite element methods and a linear one for the simple compression. The accuracy of the stiffness for plastic deformation of powder particles in plane-strain compaction is compared with that for a model experiment using aluminum rod.