Study On Thermo-plastic Forming Simulation And Heat Treatment Process Of Double Corn Thin-walled 7A04 Aluminum Alloy Component

In order to study the mechanical property of the double cone thin-walled 7A04 aluminum alloy,software Deform-3D was used to analyze its rule of metal flow,load variation,and field distribution during the forming process on the basis of identified extrusion forming scheme,billet's type and process parameters' range.The effects of deformation temperature,shape and size of billet,deformation speed and lubrication conditions on the forming results were also studied to determine the optimum parameters of extrusion process.According to YST 591-2006,the range of heat treatment process parameters was determined to meet the expected mechanical properties of the component.Then different solid solution and aging treatment were carried out after the component's formation.By comparing the mechanical properties and observing the microstructure,the most suitable process parameters were determined.The results show that:compared to columnar blank and perforated sheet,tubular blank requests the smallest load and euivalent strain.The final certain size of tubular blank is 31mm diameter,thickness 10mm,height 76.5mm.After comparing the total results,the optimum extrusion temperature is 485?.Extrusion speed of first 120mm stroke and the subsequent is 20mm/s and 5mm/s seperately.Solution treatment can make the second phase in 7A04 aluminum alloy dissolved more sufficient.In the subsequent aging process,the strength of the alloy is greatly enhanced by precipitation strengthening.The solution temperature and aging temperature have great effects on the strength of the alloy.With the increase of solid solution temperature,the number of the second phase in the matrix decreases,the particle becomes smaller,and the degree of saturation of the alloy increases,but the grain has different degrees of growth.After a comprehensive comparison,the alloy sample,treated with solution treatment at 460? for 1h and 480? for 1h followed by aging treatment at 130? for 16h,shows the best mechanical properties with the values of Rm 659.6MPa,Rp0.2 608.8MPa and A 12.79%,respectively.