Abstract: During the last two decades, high-speed railway has been developing rapidly. However, as the key walking part of high-speed railway, wheels with characteristics of open service environment and the increase of vehicle speed and axle load, have suffered more severe and complex damage. Starting from the wheel/rail contact problem, main damage behaviors of highspeed railway wheels, such as wear and fatigue, are summarized. It is found that thermal elastic instability beneath wheels tread caused by mechanical heat exchange between wheels and rails, is the fundamental reason of wear. However, unlike slow damage process of wear, repeated changes of stress magnitude and direction caused by material composition and mechanical loading during service lead to fatigue initiation and propagation, and forms of wheel fatigue are more various and destructive. Based on the analysis of thermal elasticity and internal texture of surface/sub-surface materials by using the plastic rheology theory, wheel characteristic responses of microstructure related to wear and fatigue degradations are revealed, which provides a theoretical support for wheels molding design and service safety assessment.

Key words: high-speed railway wheel, wear, fatigue, plastic rheology, crack propagation