Titanium alloy has good comprehensive performance and is a kind of excellent structural material, which is widely used.However, the cost performance of titanium alloy is relatively low, the parts are not easy to machining, high cost.Through the casting method, especially precision casting, the parts with complex shapes can be directly manufactured, eliminating a large number of machining procedures, and the utilization rate of materials can be increased to nearly 90%.
The cast titanium alloys are usually divided into a, a+B and alloy according to the phase composition, and the cast high strength, heat and corrosion resistance titanium alloys according to the custom.Among them, ti-6ai-4v and t5ai-2.5sn are widely used in casting titanium alloys, which are characterized by moderate strength, heat and corrosion resistance, and good plasticity, especially suitable for aerospace engine and structure castings.The foundry Ti6242 alloy (ti-6ai-2sn-4zr-2mo) developed in the United States can work below 500℃ and can be used in compressor parts of aero-engines, accounting for more than 2% of the cast titanium alloy.ZTC6 in China is a near - temperature titanium alloy developed by reference to Ti6242 alloy. The aluminum content of this alloy is controlled below 8%, and the high temperature thermal stability is good. It has been applied to engine parts below 500℃.ZTC3(ti-al-mo-si series) can also be used for a long time below 500℃. Due to the addition of rare earth element Ce, the alloy has good heat resistance.Cast Ti153 alloy (ti-15v-3al-3cr-3sn) belongs to metastable b-type high-strength titanium alloy, which is capable of solid solution and aging strengthening. The strength of the alloy can reach more than 1,200mpa, and the elongation of the alloy is more than 5%.ZTC5 alloy is a high strength titanium alloy developed by our country. It is a type a+ casting titanium alloy developed on the basis of ti-al-mo-sn-zr series heat-resistant titanium alloy. By adding rapid eutectoid elements, the strength of the alloy during aging is improved.