シャリップ破壊も含めた延性破壊過程の研究

抄録

Three point bend specimen with different thicknesses are used for ductile fracture tests. By the change of the specimen thickness, size of the shear-lip fracture zone near free surface also changes. Detailed observation of fracture surface is conducted, and number of voids and their sizes are measured at many locations along the crack affront. The differences of microscopic fracture patterns between dimple fracture zone and shear-lip fracture zone are studied. Numerical simulation is also conducted and stress distributions around the crack tip are obtained. Distribution patterns of stress triaxiality and principal shear stress correspond well with the dimple fracture zone and shear-lip zone, respectively.