Mechanisms of sliding wear of metals and alloys at elevated temperatures

Sliding wear at elevated temperature is an important material removal mechanism in large number of engineering applications such as metal forming operation, gas turbine engines, etc. The material loss during sliding at elevated temperature is governed by the antagonistic effect of wear process and oxidation. The objective of the present work is to give an outline of the current status and future trends of wear at elevated temperature of selected metallic materials. Starting with a brief overview of present level of understanding of the elevated temperature wear of various metals and alloys, the initial parts of the paper describes various important development in recent years on elevated temperature sliding wear. The salient features which have helped us to gain in depth scientific knowledge of elevated temperature wear are discussed in the light of recent developments. The overview is further substantiated by detailed study and observation in recent times in particular, the work done at the Vienna University of Technology (Institute of Microtechnique and Precision Engineering) and at the Austrian Center of Competence for Tribology. Specific examples from the recent literatures are described to exemplify the mechanisms of formation of various types of layers during high-temperature wear. Some thoughts on the future directions for research are also outlined.