Strain-rate sensitivity and fracture mode of V-5Cr-5Ti alloy

The strain-rate sensitivity of V-5Cr-5Ti alloy was investigated in the strain-rate range 10-4-10-1 s-1 at room temperature. The rate sensitivity decreased with the increase of plastic strain, which was qualitatively explained by dislocation thermal activation theory combined with a dislocation multiplication model. A modified Johnson-Cook model was developed to characterize the strain-rate dependence. Scanning electron microscopy of the fracture surfaces revealed that the dominant mechanisms of fracture were intergranular fracture and dimple rupture.