CHARACTERIZATION OF STAINLESS STEEL FIBER REINFORCED ALUMINUM COMPOSITE USING ULTRASONIC NONLINEARITY

Abstract

A 304 stainless steel short fiber reinforced aluminum composite was fabricated and investigated for matrix voids as well as interfacial reaction using ultrasound. The aluminum composite was made by a hot isostatic pressing technique at a temperature of 600 degrees C and subsequent aging at 120 degrees C. The tensile strength significantly increased with the addition of 5% stainless steel fiber. The interfacial reaction evolved and grew with aging time due to generation of intermetallic FeAl(2). The ultrasonic nonlinearity (beta/beta(0)) increased with the volume fraction of fiber and aging heat treatment because of the generation of microvoids resulted from localized fibers and matrix precipitation. This study demonstrates the potential for characterization of reinforced composite materials fabricated by the powder metallurgy technique.