Simultaneous strength-ductility enhancement in as-cast Ti6Al4V alloy by trace Ce

Impurity elements always play a major role in hindering mechanical property improvement Ti6Al4V, and specifically most of them e.g. O, P, Cl, S dissolved the matrix deteriorate properties Ti6Al4V. This work presents strategy enhancing performance as-cast Ti6Al4V alloy by adding small amount rare earth (i.e. 0.1 wt% Ce), where deleterious could be absorbed from crystalline lattice during solidification process, forming uniformly distributed Ce-rich oxides or precipitates with ?200 nm size. The turn refine beta phase lamellae introducing more nucleation cast alloy, which further enhances strength. As such, Ce addition exhibits tensile strength 957 ± 47 MPa elongation 12.3%, simultaneous strength-ductility enhancement compared counterpart (787 65 8.8%). In addition, also pin dislocation motions, effectively shields stress concentration at crack tip deflects propagation fracture process.