Abstract: TA10 titanium alloy was heated at 860 ℃(in the two-phase region) and at 900 ℃(in the single-phase region), respectively, and then water cooled, air cooled and furnace cooled. The effect of different cooling methods on the microstructure and impact property of the TA10 titanium alloy was studied by means of optical microscope, scanning electron microscope, XRD and impact test. The results show that when the heating temperature is in the two-phase region, the alloy forms a bimodal structure after water and air cooling, and an equiaxed structure after furnace cooling. After heating at different temperatures, under different cooling methods, the impact property of the alloy after furnace cooling is the best, followed by air cooling, and that after water cooling is the worst. When the heating temperature is 860 ℃ in the two-phase region, the impact absorbed energy of the alloy after furnace cooling is the best and the maximum impact absorbed energy is 88 J. The fracture under three cooling methods is dimple morphology when the alloy is heated at 860 ℃. The size of dimples in the fracture under furnace cooling condition is the largest. When the heating temperature is 900 ℃ in the single-phase region, the alloy forms a fine lamellar β transformed microstructure after water cooling and air cooling, and coarse β grains appear. After furnace cooling, coarse lamellar β transformed microstructure is formed, and the α phase on grain boundary is obviously coarsened. The fracture under three cooling methods is rock-like morphology, and dimples with shallow depth and small size are distributed on the surface.

Key words: TA10 titanium alloy, cooling method, microstructure, impact property, fracture morphology