Study on Tensile Properties of Ti-0.3Mo-0.8Ni Titanium Alloy for Oil Pipeline at Different Temperature

The tensile properties of Ti-0.3Mo-0.8Ni pipe tested at various temperatures were studied, and the fracture morphologies of the samples after tensile tests were investigated. Stress–strain curves of Ti-0.3Mo-0.8Ni titanium alloy at room temperature 40 and 120 °C exhibited four stages: elasticity, yield, plasticity, and necking. With the increase in temperature, the elastic stage remained essentially unchanged, while the yield point decreased and the plastic stage and necking stage noticeably prolonged. The fracture mode of titanium alloy at all temperatures was a ductile transgranular fracture, with observable cleavage platforms. Tensile fracture consisted of dimples of different sizes, and with the increase in temperature, the average dimple size increased.