Effect of functionally graded material on frictionally excited thermoelastic instability

Thermoelastic instability (TEI) is investigated focusing on the effect of functionally graded materials (FGM) where the FGM half plane slides against a homogeneous conducting or rigid non-conducting body at speed V. Results confirm analytically that there is maximum critical speeds occurring at a certain value of non-homogeneous parameter of FGM within a range of thermal conductivity, which was reported previously in the simulation model [Y.H. Jang, S.-H. Ahn, Frictionally-excited thermoelastic instability on functionally graded material, Wear 262 (2007) 1102-1112]. The effect of non-homogeneous parameters for FGM on thermoelastic instability shows that the non-homogeneous parameters of the elastic modulus and thermal expansion coefficient are strong influential factors. It is also found that when the non-homogeneous parameters of FGM range between two positive bounded values, unconditionally stable behavior is shown for a range of thermal conductivity.