Study On Microstructure And Mechanical Properties Of Magnesium Alloy Prepared By Continuous Variable Cross-section Recycled Extrusion

The CVCE(Continuous variable cross-section recycled extrusion,CVCE)technology of extruded AZ31 magnesium alloy extrusion deformation,the effect of CVCE technology on Microstructure and mechanical properties of AZ31 magnesium alloy.By using optical microscope,the grain size of XRD technology of AZ31 magnesium alloy,the microstructure of grain orientation characterized respectively along the horizontal direction and the axial direction of the microhardness and tensile test.And the DOFORM finite element The numerical simulation of AZ31 CVCE process is carried out by software,and the main results obtained are as follows:By numerical simulation and experimental study on extrusion of AZ31 magnesium alloy extrusion CVCE to determine the optimal parameters.The deformation speed is 2 mm/s,1 to 3 cycles of extrusion temperature was 350 ?,330 ? and 300 ?,the holding time corresponding cycle were 13 min,11 min and 10 min.With the increase of the cyclic deformation,the grains are refined and the microstructure uniformity is improved,but with the increase of the number of cycles,the abnormal grain growth phenomenon.The grain orientation changed by changing the orientation,each have a strong base material surface texture transformation is only strong basal texture,and texture direction is parallel to the c axis of the crystal grain of AZ31 magnesium alloy in the horizontal direction,the tensile strength of deformed specimens was increased,but the elongation rate decreased;in the axial deformation,the tensile strength and elongation are improved.Using DEFORM software of temperature field on deformation optimum process parameters,stress field,strain field simulation of metal flow and the direction of conversion between deformation and thermal deformation process,with the increase of cyclic strain deformation accumulation,deformation cycle is 5,the middle parts of the sample strain accumulation can reach 4,and the distribution is more uniform.