混合モード荷重下の異材界面き裂

抄録

In order to estimate the fracture toughness of a ductile bimaterial with an interface crack under mixed mode loading, an elastic-plastic finite element calculation based on finite strain theory is carried out under the assumption of small scale yielding and plane strain condition. The modified Gurson's constitutive equation and the element vanish technique introduced by Tvergaard et al. are used to simulate the crack growth due to ductile fracture. The results shows that the values of the fracture toughness of bimaterial are not only much lower than those of homogeneous material, but also vary greatly with mixed mode ratio and take the minimum value at a certain critical ratio.