Research On Evolution Of Spinning Texture Of 3A21 Aluminum Alloy Cylindrical Parts

It is an effective method to manufacture large-scale thin-walled seamless cylindrical parts.It has been widely used in aerospace,aviation,weapon,and so on.It has the advantages of easy maintenance,Ships and machinery and other industrial fields.As the spinning deformation process is very complex,many factors,so far,a large number of spinning technology research work is still located in the parts forming,spinning defects and geometric precision control,parts mechanical performance control considerations less.The mechanical properties of a single crystal usually have anisotropy,and the crystallographic texture can have a significant effect on the mechanical properties of the metal material,and the texture becomes one of the important means to control the mechanical properties of the material.In this paper,the multi-pass unidirectional and two-way spinning experiments are carried out by annealing the seamless seamless 3A21 aluminum alloy pipe,and the mechanical properties and spinning texture of the cylindrical parts are studied.ABAQUS The finite element simulation of the pr essure process is carried out,and the deformation history of the spinning cylinder is extracted by the user material subroutine VUMAT,and then the polycrystalline model is established by the UMAT realization rate.The strain-strain curve is used to determine the shear deformation parameters of the aluminum alloy at room temperature.The deformation gradient is extracted and loaded onto the polycrystal model.Based on the theory of crystal plasticity,the multi-Simulation of deformation of deformation.Comparison between simulated texture and measured texture.After the multi-pass spinning experiment,the microstructure evolution of the spinning parts was observed.A small amount of the second phase in the multi-pass spinning process was always distributed at the grain boundary,and its content did not affect the statistics of the crystallographic texture.When spinning to the second pass,the grain in the ND direction is similar to the uniform distribution of grain in the RD direction and TD direction equal to the elongated.From the fourth pass to the lower 8 times,the grain mainly along the RD direction elongation to form long strip of grain,along the TD direction there is a certain elongation,with the grain refinement to form a water flow;from Mechanical properties of the law of change,for the two-way spinning,spinning parts ring compression yield strength is higher than the axial compression yield strength,spinning parts ring tensile strength and axial tensile strength and did not produce a big gap,The circumferential tensile strength is slightly higher than the axial tensile strength.It can be seen that the two-way spinning is effective to control the grain orientation and improve the deformation resistance of the cylinder.The three-dimensional finite element simulation of multi-pass unidirectional unidirectional and two-dimensional spin deformation of 3A21 aluminum alloy cylinder was carried out.The stress and strain distribution of outer surface and shaft section after spinning were analyzed.And the deformation of the periodic characteristics of the superposition of cylindrical deformation of the material to bear the direction of the ever-changing tensile,compression and shear of the composite deformation.Compared with the simulated texture and the measured texture obtained by multi-pass spin-over finite element simulation,the evolution of spin-oriented grain orientation is analyzed.At the beginning of deformation,the crystal orientation of unidirectional and bidirectional spinning becomes obvious {110} <112> With the increase of the thinning rate,the grain orientation is gradually close to the hardened phase,to the 4th,6th and 8th pass,the metal orientation is no longer a single texture,but gradually formed {110} <112> {112} <111>,{123} <634> and other types of textures.We also found that the texture of the material was similar in the same deformation,and the texture distribution of the unidirectional spinning was relatively diffuse compared with the two-way spinning,and the relative two-way spinning pressure was low,so the two-way spinning had better regulation Grain orientation of the role of the deformation of the cylinder to improve the resistance.