Structural Analysis and Optimization of Heavy Vehicle Chassis Using Aluminium P100/6061 Al and Al GA 7-230 MMC

A chassis is one of the vital parts of a heavy motor vehicle, which provides rigidity to the vehicle and improves structural stability and rigidity for accurate handling. The design and material of a chassis structure significantly affects its strength and weight. Optimization techniques can be used in systematic design improvement of chassis to meet industry requirements. The current research is intended to optimize the design of chassis using the Box-Behnken design scheme and the material tested is P100/6061 Al and Al GA 7-230 MMC. Different design points were generated using the design of the experiments. Equivalent stress, deformation and mass were evaluated for each design point. The variable selected for optimization using the Box-Behnken scheme was cross member width. The CAD modelling and FE simulation of the heavy motor vehicle chassis were conducted using ANSYS software. From the optimization conducted on the chassis design, response surface plots of equivalent stress, deformation and mass were generated, which enabled to determine the range of dimensions for which these parameters are maximum or minimum. The sensitivity plots of different variables were generated, which has shown that cross member 2's width has a maximum effect on equivalent stress and cross member 3's width has a minimum effect on equivalent stress, whereas for total deformation, cross member 3 shows the maximum sensitivity percentage, which signifies that cross member 3 has the maximum effect on total deformation, and vice versa. The use of the aluminium metal matrix composites P100/6061 Al and Al GA 7-230 MMC aided to reduce the weight of the chassis by 68% and 70%, respectively, without much reduction in the strength of the chassis.