Numerical Simulation Of Once Cross Wedge Rolling On The Billets Of Aluminum Alloy Connecting Rod

Cross wedge rolling (referred CWR) is one of the most efficient methods for producing shaft parts. It has gotten extensive attention due to its high production efficiency, excellent products quality and low equipment load, etc. However, the unified conclusion in deformation mechanism and defect control has not been formed owing to the complexity of mold design and deformation law. Therefore, this method still deserves further researches.The scholars mainly utilize steel as raw material to research on cross wedge rolling nowadays, but other materials were ignored. While it is the high-strength aluminum alloy connecting rods that is widely used as mechanical parts. Therefore, combining the method of thermal-force coupled finite element simulation, this article will take engine aluminum alloy connecting rod performs as the research object and adopt the once cross wedge rolling process to explore the deformation law, thus providing a reference for cross wedge rolling process on other aluminum alloy shaft parts.The analysis shows that the metal on the surface of pieces is under compression in two directions and tensile stress in one direction. The uneven metal radial flow makes central portion of the pieces under tensile stress, the quality of materials in the core part is susceptible to damage under such stress and strain state. The metal flows to Z direction easily and deforms violently because of the large tensile stress in z direction, strain in x/y/z direction, equivalent strain and metal longitudinal flow on the joint of rolled piece and small head. Stress, strain and metal flow situation has improved with the increase of broadening angle on the joint of rolled piece and small head, thus avoiding necking effectively. With the decreasing initial rolling temperature or temperature gradient on the surface, non-uniform metal flow is balanced and the tensile stress in x direction and z direction is reduced in core portion of rolled piece, but the equivalent stress and equivalent strain increases, making loose appear more likely. Contrast with secondary cross wedge rolling process, once cross wedge rolling could improve processing efficiency and the quality of core parts on rolled piece significantly.