Titanium alloys are widely used in aerospace, aviation, […]
Titanium alloys are widely used in aerospace, aviation, shipbuilding and other fields because of their high specific strength, high temperature resistance, and corrosion resistance. At present, TC4 alloy is still the most used titanium alloy. For ordinary TC4 titanium alloy forgings, the production process is relatively mature, while the TC4 special-shaped forgings used in a certain model of aerospace are of higher quality, strict performance indicators, and complex forging processes. The forging process of the special-shaped forgings needs to be studied during the production process. The forging process influences the microstructure and mechanical properties of forgings, so as to formulate the most suitable forging process. Technicians studied the influence of two types of forging processes on the microstructure and tensile properties of TC4 titanium alloy special-shaped forgings for aerospace use.
Among them, the heating temperature of the first fire and the second fire in the type Ⅰ forging process are both in the β single phase zone, the heating temperature of the first fire in the type Ⅱ forging process is in the β single phase zone, and the heating temperature of the second flame is in the (α+β) two Phase high temperature zone. The experimental results show that the lamellar structure with coarse grains is finally obtained under the type Ⅰ forging process. The strength and plasticity of this type of structure are low and cannot meet the index requirements; the type Ⅱ forging process is adopted, that is, the second fire heating temperature is two phases at high temperature. Zone and the use of a large forging ratio can obtain a fine mixed structure composed of strip α and fine equiaxed α, which has good tensile properties and meets the index requirements. In forging, the method of reversing the length and upsetting can ensure the uniform macrostructure of the special-shaped forging.