Forging is a forming processing method that applies external force to titanium metal blanks (excluding plates) to cause plastic deformation, change size, shape and improve performance, and is used to manufacture mechanical parts, workpieces, tools or blanks. In addition, according to the way the slider moves, there are vertical and horizontal movements of the slider (for forging of slender parts, lubrication and cooling, and forging of parts for high-speed production), and the compensation device can increase the movement in other directions. The above methods are different, and the required forging force, process, material utilization, output, dimensional tolerance and lubrication and cooling methods are different. These factors are also factors that affect the level of automation.
According to the way the billet moves, forging can be divided into free forging, upsetting, extrusion, die forging, closed die forging, and closed upsetting. Because there is no flash in closed die forging and closed upsetting, the utilization rate of materials is high. It is possible to complete the finishing of complex forgings with one process or several processes. Since there is no flash, the force-bearing area of the forging is reduced, and the required load is also reduced. However, it should be noted that the billet cannot be completely restricted. For this reason, the volume of the billet should be strictly controlled, the relative position of the forging die should be controlled and the forging should be measured, and efforts should be made to reduce the wear of the forging die.
According to the movement mode of the forging die, forging can be divided into pendulum forging, pendulum swivel forging, roll forging, cross wedge rolling, ring rolling and cross 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 pre-process processing of slender materials. Rotary forging, like free forging, is also partially formed, and its advantage is that compared with the size of the forging, it can be formed even when the forging force is small. In this kind of forging method including free forging, the material expands from the vicinity of the die surface to the free surface during processing, so it is difficult to ensure the accuracy. The forging force is used to obtain products with complex shapes and high precision, such as forgings such as steam turbine blades with many varieties and large sizes.
In order to obtain high precision, attention should be paid to prevent overload at the bottom dead center, control speed and mold position. Because these will have an impact on forging tolerances, shape accuracy and forging die life. In addition, in order to maintain the accuracy, attention should also be paid to adjusting the clearance of the slider guide rail, ensuring the rigidity, adjusting the bottom dead center and using the auxiliary transmission device and other measures.
Titanium forging materials are mainly pure titanium and titanium alloys with various components. The original state of the material includes bar stock, 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. Correct 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 a great relationship with improving product quality and reducing costs. Generally, round or square bars are used as blanks for small and medium-sized forgings. The grain structure and mechanical properties of the bar are uniform and good, the shape and size are accurate, the surface quality is good, and it is convenient to organize mass production. As long as the heating temperature and deformation conditions are controlled reasonably, forgings with excellent performance can be forged without large forging deformation.