Theoretical and Numerical Analysis on Material-Stiffness Characteristics for Thin-Walled Beams on Vehicles

In order to study the lightweight effect of different materials on vehicle, we first took the two-end-fixed thin-walled beam as the research object and the Stiffness Mass Efficient as the corresponding criterion. According to the FEM simulation with four different materials conducted on thin-walled beam, the theoretical conclusion was proved coincident with the numerical one. Focusing on vehicle body-in-white, its material of beams was chosen as a variable in FEM analysis, and the relation between material attributes and body stiffness was acquired. It is noted that the magnesium-silicon alloy and the Pan-Base Carbon Fiber Reinforced Composite can achieve better lightweight effect than that of mild steel, while the classic aluminum alloy can not realize lightweight without necessary structural optimization.