Experimental Study And Analysis Of Influencing Factors On Lifetime Of Metal Rubber Isolator Under Random Vibration

Metal rubber isolator owns quite good performances of vibration absorbing, highdurability in erosive media, resistance to high and low temperature, resistance againstaging etc. With the increasingly widely use in aerospace and national defense, it’sbecoming urgent for the study of its lifetime and fatigue failure. On one hand, it’s veryimportant to understand metal rubber isolator’s lifetime under specific load thus toavoid great loss caused by failure. On the other hand, to obtain metal rubber’s failuremodels is of great importance to know metal rubber’s inner mechanism of damping thusto extend metal rubber’s application areas.Considering that metal rubber isolator works mostly under random vibration, thusstudied with ring-like metal rubber under random load. For influencing factors chosemetal rubber’s relative density, metal wire’s diameter and metal rubber’s relativepreload. By building orthogonal experiments for different influencing factors, differentfactors’ impact for metal rubber isolator’s lifetime, stiffness and transfer ratio wereobtained.Besides, plenty of lifetime experiments were carried out, got metal rubber isolators’lifetime curves. By establishing lifetime prediction models, got lifetime predictionequations for different influencing factors and, eventually, a lifetime prediction equationcovering all three factors. The comparison of the experimental data and the calculatedlifetime shows that the equation can predict metal rubber isolator’s lifetime withincertain limits.To study different failure mechanisms under various stress, SEM photos fordifferent metal rubbers were took. With the help of the microscopic view of friction onthe surface of metal wire and its fracture, studied metal rubber’s fatigue failuremechanisms. Two hypothesis were raised for metal rubber’s failure: dry friction failureand structural fatigue failure.Metal rubber is an anisotropic material, in order to carry out finite element analysis,studied ring-like metal rubber’s elastic modulus and damping ratio. By doing simulationstudy with ANSYS, got metal rubber’s stress and strain for random vibration and staticforce respectively, having a better understanding of metal rubber’s stress when subjected to force.