THE PHYSICS OF METAL MATRIX COMPOSITES

ALUMINUM/SILICON CARBIDE PARTICULATE COMPOSITES PROMISE TO PROVIDE COST-EFFECTIVE PERFORMANCE IMPROVEMENTS FOR HIGH-PERFORMANCE MISSILES. HOWEVER, IN ORDER TO AVOID RISK IN THESE DEMANDING APPLICATIONS, MORE INFORMATION IS NEEDED ON THE HIGH-TEMPERATURE MECHANICAL PROPERTIES OF THESE MATERIALS. IN THIS PHASE I EFFORT, EXPERIMENTS WILL DETERMINE THE DEPENDENCE OF COMPOSITE STRENGTH ON TEMPERATURE AND STRAIN RATE. FAILURE MECHANISMS WILL BE INVESTIGATED BY FRACTOGRAPHY, AND KINETIC PARAMETERS (SUCH AS ACTIVATION ENERGY, STRAINRATE EXPONENT, AND ACTIVATION AREA) FOR PLASTIC DEFORMATION OF AL/SIC(P) WILL BE DETERMINED. THE PROJECT WILL PROVIDE QUANTITATIVE INFORMATION ON THE KINETICS OF FAILURE PROCESSES, WHICH WILL ALLOW USERS OF THIS MATERIAL TO PREDICT MATERIAL PERFORMANCE IN MISSILE SYSTEMS AND SIMILAR APPLICATIONS.