Research On Big Modulus Spline Cold Extrusion Process

Spline is widely used in the power-transmission device of automobile. And open-die forward extrusion is a more advanced way of deforming spline. It's the key to analyze the forming feasibility, select the suitable process parameter and forecast the capable ductile fracture in open-die cold extrusion of spline.Open-die cold extrusion is applied to the big-modulus spline. The effect of the spline reduced rate and the die sharp to the forming limit is found by analyzing the limit of the extrusion. The design rules of the rough and die parameters are discussed.The article is base on the rigid plastic FEM, builds the three-dimensional mold by CATIA, and simulates the forming progress of the spline. Estimating the dentiform sharp by the minimum distance in the DEFORM-3D . The article firstly finds the fracture of the dentiform root. According the continuum damage mechanics, the fracture is forecasted by the damage value. The concave die half-angle, sharp of the die entrance, the angle in the front of the rough, and the frictionfactor effect the happen of the fracture. Extrusion experiment validates the feasibility the value of fracture- D f, to judge the occurrence of the fracture.