Guided Interface Waves

Abstract

Many of tomorrow’s technologies are dependent upon the emergence of new advanced materials with superior stiffness and strength but reduced density. Metal matrix composites (MMC’s) consisting of light metal matrices (e. g., aluminum, titanium or magnesium) reinforced with very stiff ceramic fibers or particles (e. g. SiC, AI₂O₃ or graphite) show considerable promise for satisfying this need. However, the satisfactory performance of these materials has been found to be critically dependent upon the attainment of optimal properties at the metal-ceramic interface; a problem that is compounded by the possibility of chemical reactions between the reactive metal matrix and ceramic reinforcement. Of particular import are the interface adhesion and local elastic properties. Unfortunately no methods exist for the measurement of these quantities even for macroscopic interfaces let alone for the microscopic interfaces occurring within MMC’s.

*Guest Scientist, The Johns Hopkins University, Baltimore, MD 21218