Study On The Folding Defects Formation Mechanism For Forging The Part With Branch

Due to the complicated structure and strict requirements of mechanical properties, the branch-type parts is the key structural components used in engineering field, mainly adopting extrusion technique for forming. Different types of defects are often formed in the process of extrusion forming, and among them one of the most frequently occurred defect is folding defects. Therefore, it is urgent to study the production process and the critical condition for the folding defects of branch-type parts.Aiming at the folding defects of branch-type parts in the process of extrusion forming, this paper adopted the combination of FEM method and experimental method. Firstly, the extrusion process of branch-type parts was simulated by using DEFORM-3D platform, using the finite element node tracing method to track the evolution of folding defect. By studying the distribution characteristics of strain field, velocity field, temperature field and the load curve, it revealed the metal flowing laws during extrusion and explored the formation mechanism of folding defects. Secondly, by using the method of numerical simulation, the author studied the effects of technical parameters for generating defeats such as extrusion punch shape, coefficient of friction, extrusion speed, corner radius, number of branches, twigs inclination, and branches angle. Then the curve relationship between the folding length and the technical parameters were established in order to obtain the sensitivity of the critical parameters technical parameters to the folding defect. At last, according to the analysis of numerical simulation, the physical experiment was carried out for studying the folding defects during the extrusion process to make clear the influence law of punch shape, friction coefficient and branches angle on the folding defects.Based on the studying of folding defects in extrusion of branch-type parts, this paper provided an important theoretical reference for the realization of such forging quality control.