Calibration of a ductile damage model dependent on triaxiality and Lode angle parameter

Resumo

This paper presents a numerical study using the Finite Element Method (FEM) to model the ductile
fracture in ASTM A285 Gr. C steel through calibration of a phenomenological damage model. The calibrated
damage model is composed of a damage initiation criterion dependent on the stress triaxiality and the Lode angle
parameter coupled with a post-initiation damage evolution law. A series of experimental tests on round bars
having smooth and notched cross-section, flat notched specimens under axial tensile loads, and fracture
toughness tests in deeply cracked bending specimens SE(B) were carried out to calibrate the elastoplastic
response and the damage parameters. Verification of the calibrated parameters is performed using a SE(B)
sample having a shallow crack size ratio. The agreement between the experimental tests and the numerical model
results is quite good. The adopted numerical procedure can be used to predict the response of a more complex
structure.