Study On Accelerated Aging And Failure Mechanism Of Silicone Rubber

Silicone rubber sealing materials, because of their excellent performance, aregradually replacing traditional materials and widely used in various sealing devices.They are known for their aging and degradation problems, and have been anongoing source of stockpile reliability problems even when service life is relativelyshort. Based on the time-temperature equivalence principle, the use of acceleratedlife test is to predict the sealing material is one important means. The principle ofdetermining the temperature and time is to ensure that the accelerated agingmechanism of silicone rubber is consistent with its long-term natural failuremechanism.In this paper, a typical silicone rubber sealing material for the study, atdifferent temperature and time conditions, to carry out a silicone rubber sealingmaterial thermal oxidation accelerated aging test. Consider the influence ofhumidity on the silicone rubber material performance, conducted heat aging testsilicone rubber material research. Study the variation of compression set andhardness of silicone rubber material, based on the activation energy changes ofmaterial to determine maximum temperature of silicone rubber in the heat ofoxygen accelerated aging. XPS and solid-state NMR techniques were used toanalyzing the elements variation and changes in the chemical structure of siliconerubber material, reveals the mechanism of aging silicone rubber material. Accordingto investigating the variation of compression set, established the prediction model ofthe silicone rubber, by comparing the results, the lifetime predict in this paper iswell consistent with the natural aging results.This study revealed the aging mechanism of silicone rubber material,determined a reasonable upper limit of the accelerated aging test temperature,provided a reasonable lifetime forecasting model of silicone rubber material toaccurately predict the service life of the sealing material foundation.