Concept Analysis of Automotive Aluminium Alloy Bumper

Abstract

One style of aluminium alloy bumper was developed for a passenger car. Firstly, strength performance objective was obtained through three-point static pressure simulation analysis and test on steel bumper of a target vehicle. In order to provide reference for aluminium alloy bumper on the design of structure and performance, benchmark analysis was applied on a reference aluminium alloy bumper. Then, the cross-section shape and dimension parameters of aluminium alloy bumper of target vehicle were obtained with OptiStruct topology optimization and size optimization, so that the material, process method and processing parameters of components of the production can be determined, among which, 6,061 aluminium alloy was employed for producing bumper beam with hot extrusion process, and 6,101 aluminium alloy was employed for producing crash box and flange with hot extrusion process. At last, low-speed collision simulation and test were used to analyze the energy absorption capacity of steel and aluminium alloy bumper. It has been found that: in the process of head-on collision, the energy absorption of aluminium alloy bumper is higher than that of steel bumper with increasing 5 %; the absorption per unit mass of aluminium bumper is significantly greater than that of steel bumper, and its deformation is 110 mm less than the permission displacement. Consequently, it is concluded that the crashworthiness of aluminium alloy is better than that of steel bumper. In this paper, an aluminium alloy bumper was designed by using topology optimization and size optimization method, which has better performance, compacter structure and lighter weight than that of steel bumper. However, in view of the complexity of the actual working conditions applied by bumper, higher requirements should be taken into account in design process. Therefore, in subsequent structural optimization research, integration of additional conditions needs to be considered, such as collision, etc.

F2012-E09-030