Abstract:

A PC/ABS alloy?based air bag cover plate with a weakening groove of ‘H’ type was selected as a research object, and its finite element model was constructed. The reliability of finite element model was verified by comparing the results of finite element mechanical simulation analysis with theoretical calculation. Through the integration of CATIA and ANSYS in ISIGHT software, four parameters including the lateral width and depth, and longitudinal width and depth of the weakening groove of the air bag cover were selected as the design variables, and the lateral maximum stress and longitudinal maximum stress of the weakening groove were selected as the response variables. The contribution distribution of design variables to the response variables was analyzed, and the multi?objective optimization of the response variables was carried out by the NSGA genetic algorithm. The results indicated that the lateral depth and longitudinal width had a negative contribution to the lateral maximum stress, but the lateral width and longitudinal depth had a positive contribution. On the other hand, the lateral width and longitudinal depth had a negative contribution to the longitudinal maximum stress, but the lateral depth and longitudinal width had a positive contribution. The multi?objective optimization of four parameter values were realized within the reasonable range, which could reduce the lateral maximum stress but increase the longitudinal maximum stress. This effectively reduces the amount of debris produced when the airbag cover plate explodes, thus improving the safety performance.

Key words: polycarbonate, acrylonitrile?butadiene?styrene copolymer, alloy, air bag cover plate, optimization, ISIGHT software