Cross-scale fretting failure mechanism and fatigue failure prediction of metal rubber

Abstract

Abstract Metal rubber (MR) is a kind of elastic porous material with a complex and disordered internal structure, which results in a life evaluation that can only rely on tests but cannot meet the engineering application. This paper presents an interesting life prediction method based on its virtual fabrication technology. By developing the intricate internal multipoint random contact mesh model of MR, a virtual real-time dynamic tracking contact point in the state is captured. A thorough investigation is conducted into the contact point properties, point distribution, and the interaction of discrete contact points in MR interior space. Accordingly, a cross-scale fretting failure mechanism from micromorphology to macro-performance is proposed. The continuous fatigue cycle of MR is discretized into multiple single-turn metal wire elements by applying the principle of equal spacing. A statistical model of internal contact point wear of MR at the microlayer is developed considering the metal wire's single-turn fretting wear prediction model. The cumulative prediction model of macroscopic fatigue damage of MR is based on the superposition of micro-element interval. Finally, the fitting degree between the mass loss with loss factor and stiffness degradation degree after performing fatigue tests under different periods is investigated. A fatigue failure prediction model of metal rubber is established. The results of the fatigue failure prediction models are compared with experimental data and found to be consistent.