Fracture Toughness and Its Prediction Model for Ti17 Titanium Alloy with Basket-Weave Microstructure

The fracture toughness and fracture behavior of Ti17 titanium alloy with basket-weave microstructure were studied. The results show that fracture toughness is attributed to two major factors, namely the crack path tortuosity (extrinsic part) and plastic deformation work along the crack path (intrinsic part). Good plasticity and tortuous crack propagation path are both favorable to improve the fracture toughness of Ti17 alloy. Moreover, based on the power theory, a fracture toughness prediction model was built, whose prediction error was within 6%. In addition, by analyzing the prediction results of this model, it can be found that the contribution of plasticity work to the fracture toughness of Ti17 alloy is the major part, which occupies over 80%. The contribution of crack propagation tortuosity to the fracture toughness of Ti17 alloy, however, is the minor part, which is within 20%.