Fatigue Life Prediction of a Rubber Mount Considering the Self-Heating by the Hysteresis Loss of the Rubber Material Subjected to Cyclic Loadings

Failure analysis and fatigue life prediction are important steps in the design procedure of industrial products to assure the safety and reliability of their components. A model to calculate the heat generation by the hysteresis loss in natural rubber subjected to cyclic loads in a uniaxial direction was introduced and the fatigue life prediction model of the rubber was established based on the theory of continuum damage mechanics (CDM). Dynamic mechanical analysis (DMA) was used to measure the viscoelasticity of the rubber material. The heat generation in the rubber material was calculated using a subroutine with the programming software C++ and the temperature rise in the rubber material was analyzed by a thermal finite element analysis (FEA) method. Then static mechanical FEA models of a rubber mount were established and the strain contours of the rubber mounts at various loads were calculated. The total principal strain was used as the fatigue parameter to predict the fatigue life of the rubber mount. Finally, the fatigue lives of the rubber mounts at various loads were measured on a test rig to validate the accuracy of the prediction method. The test results indicated that the fatigue lives predicted considering the temperature rise agreed better with the test results compared with those not considering the temperature rise and we suggest our fatigue prediction method should be applicable to both rubber and other types of components.