Instability of Thermoelastic Contact

Abstract

The thermal boundary conditions in thermoelastic contact problems are typically coupled to the mechanical boundary conditions. For static thermoelastic contact, surface roughness effects causes a thermal contact resistance which is dependent on local contact pressure. The effects of this thermomechanical coupling are illustrated in a simple one-dimensional rod model, which exhibits instability if the transmitted heat flux is sufficiently large. The stability problem is analyzed using a linear perturbation method which is then extended to problems in two and three dimensions. An important application concerns the development of non-uniformities in the nominally one-dimensional solidification of a metal in contact with a plane mould.Related instabilities are obtained when two bodies slide together causing frictional heating that is proportional to the local contact pressure. The stability of idealized geometries such as half-planes and layers can be investigated by analytical methods, but the perturbation problem must be solved numerically for practical geometries, such as those arising in brakes and transmission clutches. Results for such cases are compared with experimental observations of thermal damage under industrial test conditions.KeywordsContact PressureCritical SpeedHeat Conduction ProblemThermal Contact ResistanceMigration SpeedThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.