Continuum damage mechanics theory together with large deformation elastic-p
lastic finite element analysis has been used to predict crack growth initia
tion in ductile materials. The damage growth law is based on experimental o
bservations reported in the literature. A local crack growth initiation cri
terion is proposed. The criterion makes use of the critical damage as the c
ontinuum parameter and the average austenite grain size as the characterist
ic length. To test the validity of this criterion: experiments have been co
nducted on standard specimens and have also been simulated numerically. The
proposed criterion has been used to predict the values of the critical loa
d at crack growth initiation and the fracture toughness. The numerically pr
edicted values compare favourably with the experimental values. (C) 2000 El
sevier Science Ltd. All rights reserved.