Study On The Age Forming Of The Al-4.5Cu-1.5Mg Aluminum Alloy

A new molding method calls Age Forming which is designed for fabricating aircraft panels, has been developed since the middle of1980’s. The age forming technique has been applied to manufacture the aircraft panels and achieved great advantages by many famous companies, such as Boeing and Airbus. But the technic does not apply to our factories as lack of basic research work by now. Therefore, it is necessary for investigating the basic theory of the age forming.By means of mechanical properties testing, conductivity testing, TEM, SEM, DSC and optical microscopy, the overheating temperature and the dissolution of alloy phases of hot-rolled2A23aluminum alloy plate were investigated to optimal its solution treatment. The effect of aging temperature and aging time on the strength, elongation and conductivity of alloy plate were studied to get the age-hardening curves of alloy plate, moreover, to derive the mathematic relations between the maximal load and the size of sample by the same method mentioned above. On this basis, the influence of aging temperature and aging time on the age forming deformation of alloy plate was also studied. The effect of stress on the precipitate of alloy plate was summarized by analyzing the character of precipitate appearance and oriental. The main results are as follows:(1) The overheating temperature of2A23aluminum alloy is507℃, the optimal solution treatment is503℃×50min.(2) The relations between the maximal load and the size of the sample during the age forming process is:/-the length of the sample, b-the width of the sample, y0-the thickness of the plate, σ0.2-yeild stress of the plate. (3) The age forming deformation of2A23aluminum alloy plate increases slowly as the yield strength of alloy plate increased, while the deformation increases quickly as the yield strength of alloy plate decreased as the aging time prolonged.(4) The stress inhibits the precipitation of S phase while the tensile stress accelerates the precipitate of S phase, and the precipitate grow up along the direction which can counteract the tensile stress during age forming process of2A23aluminum alloy plate.