China Young Chang Jiang Scholar, Associate Professor, State Key Laboratory of Tribology, Tsinghua University, China.

Speech Title: Triboluminescence dominated by crystallographic orientation
Abstract: Triboluminescence (TL) is an optical phenomenon that has a long and varied history with broad applications, such as damage detection, X-ray source, and mass health monitoring sensor. So far, the properties and mechanisms of TL remain not completely understood. The TL properties emitted during the sliding contact between sapphire and silica surfaces were studied along different crystallographic orientations. In this study, the TL intensity was significantly enhanced as sapphire surface was along a particular crystallographic orientation, which is an unconventional phenomenon. TL enhancement was not affected by air atmosphere and atomic stocking mode of sapphire. The enhancement mechanism may be influenced by the surface state of sapphire. This work provides a new method to control the intensity of TL and novel ideas to elucidate the TL mechanism.
Keywords: Triboluminescence, crystallographic orientation, alumina