Thermoelastic instability including surface roughness effects

A thermoelastic instability (TEI) analysis is presented for determining the threshold of instability in a friction pair consisting of a conducting sur face rubbing against a rough surface with very low thermal conductivity. Th e theory predicts that TEI is initiated when the operating speed exceeds a limiting value of U* given by: U*/U-s = 1 + Lambda F where U-s is identical to the critical equation developed by Button (1980) for highly loaded surfaces in contact defined as: U-s = 2 Omega k(s)/f alph a E. The dimensionless parameters on the right-hand-side of the above equat ion emerge from the consideration of the surface roughness and are defined as Lambda = sigma Omega E/2 chi, and F' = H-o/F'. The results indicate that the magnitude of the applied load and the surface roughness characteristic s tend to play an important role in the prediction of the onset of TEI inst ability.