2226 空孔の分布状態による異方性を考慮した多孔質材料の弾塑性構成式(S03-2 材料の塑性挙動の構成式のモデル化とシミュレーション(2),S03 材料の塑性挙動の構成式のモデル化とシミュレーション)

Abstract

The elastic-plastic deformation of perforated sheet is analyzed by finite element method in terms of the modified Gurson's yield function, where the anisotropy of damaged materials is taken into account through the damage tensor and the net stress tensor. The damage tensor represents the state of damage due to distributed holes and is determined by the method using voronoi tessellation which divides a perforated sheet into many polygons. Each polygon has a hole in it and is transformed into a representative unit cell which is used to define both the damage and the net stress tensors. Perforated sheets with randomly distributed holes were set up as the plane models of damaged materials and were examined under the condition of biaxial tension. Experimental results show that the fracture pattern of perforated sheets and local plastic deformation are well described by the modified Gurson's yield function.