Effect of surface roughness on sealing performance of silicone rubber

Silicone rubber seals are widely used in the aerospace industry, and the microscopic roughness of the metal surface has a significant effect on sealing performance. In this paper, a sinusoidal profile is used to describe the microscopic topography of the metal surface. Then, a static sealing contact model is developed by the finite-element analysis software Abaqus for analyzing the influence of surface roughness parameters R _a and R _sm on sealing performance. Results show that the sealing clearance and the maximum contact pressures increase when R _a increases. However, the sealing clearance and the maximum contact pressures decrease when R _sm increases. With the decrease in R _a, the contact ratio increases in the contact interface between rubber and metal surface. When R _sm increases, the contact ratio in the contact interface increases. The contact pressure and the stress concentration increase when the surface roughness increases. Thus, it is important to consider the effect of the microscopic roughness in rubber seal design.