Ductile fracture prediction in cold forging process chains

The paper presents a new approach for the prediction of ductile fracture occurrence in multi-stage cold forging process chains. The approach combines the fracture criterion proposed by Xue and Wierzbicky with a linear damage accumulation law. Thanks to this feature, the approach is capable of predicting both the location where the failure events occur under the action of external loading and the time they take to be generated. An application to the multi-stage cold forging of a C35 Torx-type socket screw carried out on a double-blow header is presented and results of predictions are compared with experimental observations.