Local Chemistry at Interfaces and Boundaries: Ceramic and Electronic Composite Materials

Abstract

Abstract. 2014

Platinum-enhanced graphitisation in sandwich structures of silicon carbide and borosilicate glass

“…While Si atoms are consumed by the Pt 2 Si formation, C atoms diffuse through the silicide to the opposite interface with the reaction layer, where they precipitate to form graphitic lamellae. This suggestion of formation and disintegration of Pt 2 Si is also emphasised by elemental gradients, which have been found in Pt/6H-SiC-reaction couples at the interfaces of Pt 2 Si to both the silicon carbide and the adjacent carbon layer [41]. Pt 2 Si regions near the 6H-SiC has been described to be enriched in Si, whereas those near the C layer are Pt-rich.…”

High resolution interface nanochemistry and structure. Progress report, December 1, 1994--November 30, 1995

“…This effect has been observed by other authors in HREM images of 6H-Sic and attributed by them to various causes: (1) the crystal being tilted slightly off a low index zone axis when the HREM images were taken, or (2) violation of dynamical extinction rules permitting excitation of forbidden Bragg reflections which should cause the alternating contrast, or (3) solute absorption affects causing subtle changes in crystal structure that would induce the alternating contrast. The origin of the alternating contrast is clearly a complicated and important question.…”