The aerospace grade titanium alloy smelting ingot purification process is characterized in that it includes the following steps: batching, mixing and pressing electrode blocks, welding block electrode blocks, vacuum consumable electric arc furnace primary melting, true shell furnace secondary melting, vacuum consumable electric arc furnace three melting, finished ingot inspection and storage steps. Through the combination of three different melting processes, the titanium alloy material is fully alloyed, the inclusion of foreign matter is effectively removed through the casting process, which is conducive to the uniform distribution of molybdenum element in titanium alloy, effectively reduces the content of oxygen, nitrogen, hydrogen, phosphorus, sulfur and other harmful elements in TB8 titanium alloy, and effectively filters impurities for purification. The high purity TB8 titanium alloy ingot was obtained. TB8 titanium alloy ingot through multiple melting to make the alloy composition distribution more uniform, effectively prevent segregation, inclusion, can meet the needs of aerospace grade titanium alloy.
The application of titanium alloy materials in aerospace, petrochemical, shipbuilding and other fields has gradually expanded. A country's titanium alloy material preparation level has become an important embodiment of a country's comprehensive national strength.
In many titanium alloy materials, due to the limitations of traditional melting process, the performance index of titanium alloy is often difficult to reach a high level, and the good and good rate is relatively low. Among them, TB8 titanium alloy belongs to the new metastable β titanium alloy, and its nominal composition is Ti-15Mo-3Al-2.7Nb-0.25Si, which is an ideal aviation structural material, and its quality directly affects the comprehensive properties of titanium alloy materials. TB8 titanium alloy contains 14%-16% molybdenum, molybdenum melting point is 2622℃, density 10.0g/cm3, much higher than the melting point of titanium sponge 1668℃ and density 4.5g/cm3, while TB8 titanium alloy aluminum content is low. The traditional preparation process of TB8 titanium alloy is to use vacuum consumable arc furnace melting, using one, two or three times melting, even after multiple melting, but this melting preparation process still has the following shortcomings:
