Study On The Constitutive Model And Solid Boss Plate Forging Ability Of Of 6060 Aluminum Alloy

The structure with salient features plays a role in positioning,fixing,riveting,strengthening and other roles in lightweight products,and is widely used in automotive,instrumentation,electronics and electrical fields.The traditional reverse extrusion process has some problems,such as large processing load and serious shrinkage defects at the bottom of the bulge,so it is of great theoretical significance and practical engineering value to develop a new convex forming process to solve the deficiency of the traditional forming process.Plate forging is a kind of potential precision plastic forming technology,which is based on the traditional sheet metal stamping technology and integrates volume forming technology such as upsetting,extrusion and die forging,etc.Taking 6060 aluminum alloy as the research object,this paper studies the forming process of four bulking at the bottom of cylindrical parts by means of thermal drawing experiment,finite element numerical simulation,FORTRAN secondary development,deep drawing and upsetting extruder forging forming experiment.The main work contents and results are as follows:1. The 6060 aluminum alloy sheet was subjected to warm and hot tensile experiment.The forming temperature was 250?,300?,350?,400?and 450?respectively,and the strain rate was 0.001s^-1,0.01s^-1and 0.1s^-1respectively.By analyzing the experimental data,the real stress-strain curve of 6060 aluminum alloy can be obtained.By using origin and other drawing software to fit the experimental data,the Fields-Backofen constitutive equation can be obtained.Scanning electron microscope was used to observe the fracture morphology of 6060 aluminum alloy after stretching.It was found that the higher the temperature,the lower the strain rate,and the deeper the dimples on the surface of the fracture,the better the plastic property was,indicating that 6060 aluminum alloy had certain sensitivity to temperature and strain rate.2. Fortran language was used to write programs for secondary development,and field-Backofen constitutive equation was imported into Deform-3D software.Deform-3D software was used to conduct numerical simulation analysis on the forging process of 6060 aluminum alloy plate.Based on the analysis of the influence curve of the convex structure position on the formability of the four convex structures,the selection of the structure position is determined,and the influence of the die structure parameters,contact conditions,temperature,sheet thickness and back pressure load on the formability of the solid convex structures is discussed.The results show that when the thickness of 6060 aluminum alloy sheet is 2mm,the smaller the bulge radius,the smaller the friction coefficient between the punch and the sheet,and the better the bulge formability.With the increase of temperature,the forming performance of the convex improves continuously.Increasing the load of back pressure can increase the forming height of four bulges.3. Mold design was carried out according to Deform-3D simulation results,and plate forging and forming experiments were carried out on 6060 aluminum alloy cylindrical parts with four protrations at the bottom,and the accuracy and reliability of numerical simulation were verified by comparison with simulation results.