Microstructure and fatigue fracture characteristics are analyzed of gas tungsten arc welded TA15 tita鄄
nium alloy joints, and the quantitative relationship between pore defects and fatigue life is obtained. The results show
that the fatigue crack initiates from the subsurface or internal pores. When the pore size is small, the fracture will ap鄄
pear "fish鄄eye" morphology. Influence of pore size on fatigue life is particularly significant at a low level stress. Fa鄄
tigue life can be predicted through pore size at a given stress level, having important engineering significance for the
fatigue life prediction and assessment of welding quality