Extrusion Forming And Numerical Simulation Of 5A06 Aluminum Alloy Conical Parts

With the rapid increase of social and economic development and industrialization,Aluminum alloy has been widely used in aviation,aerospace,ships,buildings,bridges and other industries,Complex aluminum alloy parts have been widely developed and applied.Compared with the traditional manufacturing technology of aluminum alloy,cold extrusion technology has attracted more and more attention because of its high precision,good performance and cost saving.In this paper,the cold extrusion forming of 5A06 aluminum alloy conical parts is studied.This paper introduces the principle of cold extrusion,the law of metal flow and the factors affecting the extrusion;Modeling of conical parts using UG;Calculation and determination of the relevant parameters in the cold extrusion process;Based on the finite element theory and DEFORM simulation software,the velocity,load,stress,strain and forming process of the product were analyzed.Also,the mechanical properties and the microstructures of the part were studied by experiments,which proved the correctness of simulation results.The main conclusions are as follows:(1)Four processes are used for extrusion forming,the forming condition of the conical part is good,and the metal streamline is clear and even.During the stimulation,as the male mould depresses,the metal flow speed of die head decreases,the flow speed on the head of part increases gradually,and the flow speed of middle metal increases gradually with the increasing of the axial dimensions.The maximum speed increases to 30mm/s at the middle of the product in last step of extrusion.Likely,t he load increases regularly.At the beginning of the second extrusion,the mold needs a large pressure to press into the blank,so the initial load increases rapidly,and then increases to the maximum value.The equivalent stress and the equivalent strain distribution are uniform,and the deformation trends are relatively uniform.The maximum equivalent stress is about 386 MPa at the terminal extrusion.(2)By observing the microstructure of the squeezed alloys,we can find that the deformation and the deformation degree of the microstructure increase gradually along the extrusion direction of the part.The deformation degree of the metal on the bottom of wall filter is maximum,where the microstructure shows filamentary and it is stretched obviously along the extrusion direction.On the bottom of the final part,streamline distribution is relatively uniform because of the metal bear relatively large stress,but tissue deformation is relatively smal.(3)With the heat treatment(310? for 1 hours,air-cooling),the tensile strength and hardness of the materials decreased,the deformation resistance reduced,the plasticity and the extrudability of raw materials were increased.By studying the microhardness of the part,the metal hardness reached the maximum value of about 132.2HV in the vicinity of the conical head for the large extrusion deformation of the metals.The microhardness on the bottom of the final part is 119.6HV metal,where the value is relatively small for the relatively small deformation and annealed before the final extrusion.