Deformation Uniformity Of Sheet Hydroforming For Double Curved Shell With 2A12 Aluminum Alloy

With the continuous development of aerospace, aviation, automotive industry and other industries, high strength, lightweight, high-precision plate products continue to be put on the bill. Different from the traditional forming shells, double curved shell is a non-rotational symmetry of high-order curved surface shells, mainly used in the field of aerospace, aviation, automobile and other high-end fields.The double curved shells of 2A12 aluminum alloy were studied in this paper, and hydromechanical deep drawing not only makes the wall thickness distribution more uniform and improve the forming precision, but also can increase the strain distribution.Experiments show that the minimum wall thickness was 1.360 mm and maximum wall thickness was 1.385 mm when planar deep drawing 40 mm and punch stroked to 80% of the total trip after liquid chamber pressure reaches 10 MPa by binder surface. At the same time, the average equivalent strain was 6.22%. Equivalent strain would decrease when the liquid chamber pressure continued to increase.The average equivalent strain reached 6.90%, a minimum equivalent strain was 5.57% and the maximum equivalent strain was 8.89% with the drawing depth of 5mm and the liquid chamber pressure of 5MPa by the curved binder. In all the forming processes, it has the minimum difference between the maximum equivalent strain and the minimum equivalent and the biggest average equivalent strain.2A12 aluminum alloy is a kind of high strength aluminum alloy, which through heat treatment hardening in solid solution and aging can obtain higher strength and hardness. The tensile strength increased to 455.89-471.24 MPa, and the hardness value of Vivtorinox increased to 138.72-140.44, so as to enhance the practical application value of the double curved shell of 2A12 aluminum alloy.