A continuum damage mechanics model for void growth and micro crack initiation

A damage mechanics model is proposed to study the void growth and crack initiation. J2 incremental flow theory along with a damage variable is used to model the material behaviour in elasto-plastic regime. Large deformation (large rotation and finite strain) finite element analysis is carried out for five different cases. In all the cases it is observed that the triaxiality and the plastic strain play an important role in void growth and crack initiation in ductile material. A failure curve is obtained for the material AISI-1090 spheroidised steel. Finally, it is concluded that the critical value of the damage variable can be taken as a crack initiation parameter.

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