The advantage of casting process is that it can produce castings of any size and shape at low cost, but the use performance of castings is greatly affected by the technical characteristics of the casting process itself; the mechanical properties of forgings produced by forging process are excellent, but the process is tedious if the shape of parts is complex. The driven spiral bevel gear of the automobile rear axle researched in this paper not only has complex geometry, but also has strict requirements for its performance. The casting forging composite forming process combines the advantages of casting process and forging process, which is very suitable for machining parts with high performance and accuracy requirements and complex structure. In recent years, many countries have made great achievements in the research of casting forging compound forming technology.
When Lee K and others studied the forming process of aluminum alloy parts, they found that the tensile strength and elongation of products produced by the casting forging composite forming process were greatly improved compared with those produced by the traditional casting process. Kim HR et al. Used the casting forging compound forming process to produce the connecting rod joint of automobile steering gear. The process test shows that the hardness of the parts produced by this process after heat treatment is higher than that produced by the casting process More than 20%; Li Weidong, etc. compared and analyzed the casting forging composite forming process with other processes, and emphasized the technical problems involved in the casting forging composite forming process and the matters needing attention in the design of the die; Li Zhiguang, etc. successfully applied the casting forging composite forming process to the production of a certain type of coal conveyor 1340 In the actual production of coal scraping board, the actual produced parts not only meet the design requirements, but also have low production cost, high efficiency and good economic benefits. When Li Yaning et al. Used the composite forming process to process magnesium alloy parts, it was found that after the plastic deformation process, the internal structure of the casting workpiece generated uniform fine grains, after the heat treatment, the parts yield The strength, elongation and other mechanical properties have been improved significantly; Li Jia introduced the casting forging composite forming process into the production of automobile steering control arm, obtained the best process parameters through simulation, and the mechanical properties of the trial produced parts have been improved significantly; Ruan Falin tried to use the die forging and die casting composite process to process ad91 The forming process of magnesium alloy motorcycle wheel hub was simulated and optimized by orthogonal experiment method. The microstructure of the trial production part was found to be fine equiaxed crystal with average size up to Under 25 μ m, Gao Lin applied sand casting process and rotary ring rolling process to the processing of low-carbon steel flange parts, and got the conclusion: the second heating can significantly improve the mechanical properties of the billet, the rotary ring rolling can close the shrinkage cavity defects in the billet; Cao Zhengzheng applied casting and rolling process to Q235B In the forming process of the ring part, the solidification process of the ring part is analyzed by using the casting simulation software. The results show that reducing the pouring temperature within a certain range of temperature is conducive to refining the grain. Wang Shuncheng and others designed and manufactured the casting forging integrated forming equipment, which greatly reduced the time of using the composite forming process to produce the part and saved the production cost.