Research Of Effect Of Cross Section Geometric Features On The Rotary Draw Bending Of Aluminium Alloy Profile

With the rapid development of China’s automobile and high-speed rail industry, energy crisis and environmental pollution problems have become increasingly prominent. Lightweight structure design can effectively reduce energy consumption and environmental pollution, which is the trend of future industry development. Aluminum alloy material with low density, can significantly reduce the weight of the same volume steel structure. Therefore, Aluminum alloy profiles are increasingly used in the manufacture of automotive parts.Aluminum alloy profile bending forming process involves many complicated problems, such as geometric nonlinearity, material nonlinearity and boundary condition nonlinear. Through the combination of experiments and simulation, the influence of cross section geometric features on the warp of vertical wall profiles in bending process was studied, this paper mainly do the following aspects. Firstly, sample was cut from the test piece 6063 aluminum alloy profile by using the line cutting method. The basic mechanical properties of the materials were obtained through the uniaxial tensile test. The power exponent hardening models were used to describe the flow stress behavior of the material, and the constitutive relation of the corresponding mechanical state is established.Secondly, based on LS-DYNA software, a three-dimensional finite element model of rotary draw bending forming for vertical wall aluminum alloy profiles was established. The distribution of equivalent stress and strain with time was analyzed in the rotary draw bending process. After the test, the authenticity of the model is verified by comparing the deformation results of upper and lower arcs from the test and simulation, and the influence of gap on the warping deformation is analyzed.Finally, through the rotary draw bending forming process of several representative vertical wall profiles we can find the following conclusions. The warping deformation is asymmetrical in the same forming part, and the asymmetry of the warpage in the different forming parts is not unity. Increasing the symmetry of horizontal features outside of vertical wall profiles can be helpful to reducing warping deformation, and increasing features inside can reduce warp effectively. By designing the profile section reasonably and locating the neutral layer at the straight wall in the process of forming, the problem of warping deformation of vertical wall profiles will be solved.The application of simulation method in the bending process of aluminum alloy profile is studied, and the reliability of the simulation method is verified by the test results. Then, effect of cross section geometric features on warp in the rotary draw bending process is studied by using simulation method. This work can be referable for part design of complex surface profile and determination of process parameters of bending forming.