Effect of surface quality and notch on bending properties of Ti80 alloy

The effects of surface quality and notch on the three-point bending properties of Ti80 alloy were studied by digital image correlation method. The fracture surface was observed by scanning electron microscopy and electron backscatter diffraction. The results show that the bending strength of the surface polished sample was the largest, the bending strength of the surface polished and notched samples decreased slightly, and there was no obvious notch strengthening effect. The fracture strain decreased rapidly with the decrease of surface quality and the increase of notch size. The larger the stress concentration factor, the smaller the deformation area and the weaker the strain hardening ability of the sample. The fracture morphology of Ti80 alloy was dimple, and there were a large number of low angle grain boundaries.