Technical requirements for titanium forging process

According to the movement mode of the blank, forging can be divided into free forging, upsetting, extrusion, die forging, closed die forging and closed upsetting. Because there is no flying edge in the process of closed die forging and closed upsetting forging, the material utilization rate is high. Complex forgings can be done with one or more processes. Since there is no flying edge, the stress zone of the forging is reduced and the required load is also reduced. However, it should be noted that whitespace cannot be completely restricted. Therefore, the volume of the blank should be strictly controlled, the relative position of the forging die should be controlled, and the forging should be measured to reduce the wear of the forging die.

According to the movement mode of forging die, forging can be divided into rotary forging, rotary forging, roll forging, cross wedge rolling, ring rolling and diagonal rolling. Rotary forging, rotary forging, and ring rolling can also be processed by precision forging. In order to improve the utilization rate of materials, roll forging and cross rolling can be used as the first step of slender materials. Rotary forging, like free forging, is partially formed. Its advantage is that it can be formed even if the forging force is smaller than the forging size. This method of forging, including free forging, extends the material from near the die surface to the free surface during machining, making it difficult to ensure accuracy. Therefore, by controlling the movement direction and forging process of forging die with computer, products with complex shape and high precision can be obtained with low forging force, such as forgings for various types and large size turbine blades.

To achieve high accuracy, care should be taken to prevent BDC overload and control speed and die position. These can affect forging tolerances, shape accuracy, and die life. In addition, in order to maintain accuracy, attention should also be paid to adjusting the clearance of the slide rail, ensuring rigidity, adjusting the bottom dead center and using auxiliary transmission devices and other measures.

Titanium forging materials are mainly pure titanium and various components of titanium alloy. The original state of materials is bar, ingot, metal powder and liquid metal. The ratio of the cross-sectional area of the metal before deformation to the cross-sectional area after deformation is called the forging ratio. Proper selection of forging ratio, reasonable heating temperature and holding time, reasonable initial forging temperature and final forging temperature, reasonable deformation amount and deformation speed have important relations to improve product quality and reduce cost. Generally small and medium forgings use round or square bar material as blank. The particle structure and mechanical properties of the bar are uniform, the shape and size are accurate, and the surface quality is good, which is easy to organize large-scale production. As long as the heating temperature and deformation conditions are reasonably controlled, the forgings with excellent performance can be forged without large forging deformation.