Three-dimensional thermoelastic contact has long been an important topic in tribology. Contact is a principal method of applying loads to deformable bodies, and thermal stress often occurs during this contact due to frictional heating or temperature differences. W ith the rapid increase in the use of anisotropic materials, the demand for three-dimensional methods and formulations to solve thermoelastic contact problems for anisotropic materials has become increasingly necessary. In this dissertation, the threedimensional thermoelastic contact for both isotropic and anisotropic materials is studied.

By applying line integral of Bamett-Lothe tensors on oblique planes, the threedimensional rough surface problem for a semi-infinite anisotropic elastic half-space is formulated. The conjugate gradient technique of analytical continuation with isothermal condition is employed. The general solutions for various types of material properties are obtained. The multi-region rough surface contact model has been proposed to study the annular contact system. In addition, an extension scheme has been developed to allow the contact models to handle elastic-plastic contact problems. The results show that surface roughness can significantly alter stress distribution in the contact. Even for smooth contact problems, the peak contact stress/force will vary depending on different mechanical property orientations. The sensitivity to material constants may provide insight into better material design for anisotropic material contact conditions.