Critical comparison of popular hyper-elastic material models in design of anti-vibration mounts for automotive industry through FEA

Often a mount designer is caught between the conflicting targets of matching stiffness as well as durability in a short timeframe. This paper attempts to address challenges associated with the correlation between elastomeric mount performance and simulation results. The effects of insufficient material characterization data (type and range), calibration, chosen constitutive model and stability check on stiffness and stress/strain prediction are discussed. Coefficients are now determined using direct (least square fit) as well as weighted, using genetic algorithm based curve-fitting. A step-by-step methodology (iterative) has been developed. This method allows error to be identified and attributed to material model and/or thermal shrinkage, pre-load, mesh, or boundary conditions. Case studies are included with Neo-Hookean, 2-term Mooney-Rivlin, Yeoh and Rivlin material models using in-house nonlinear FEA software, ARC3D.