Computer simulation of fracture initiation and crack propagation of TPB specimens

Abstract

A unified damage and fracture model, the combinatory work density model, which is not only suitable for non-cracked bodies but also for cracked bodies, has been suggested [K. S. Zhang and C. Q. Zheng, On the Research with Meso-mechanics of Ductile Fracture and Its Applications, pp. 84–98; Engng Fracture Mech.(in press)] by the authors of this paper. In the present paper, the processes of fracture initiation and crack propagation of TPB specimens made of 40 Cr steel have been simulated by using the combinatory work density model combined with the large elastic-plastic deformation finite element method. The simulation results not only present the relations of loading and displacement at loading point P-Δ, the crack's extension with displacement at loading point Δa-Δ, but also present the resistance curve J R-Δa and the parameter J IC . All the results are in fairly good agreement with those obtained by experiments. Therefore it is confirmed that the model suggested by the authors can be used not only to simulate and predict crack initiation and propagation in a non-cracked body, but also to simulate and predict fracture initiation and the crack's stable propagation in a cracked body.