REACTION INTERFACES OF NICALON FIBER ALUMINUM COMPOSITE SYSTEMS - THEINFLUENCE OF FIBER PRETREATMENTS AND MATRIX COMPOSITION/

Systems composed of Nicalon NL-202 multifilament fibers and an Al-base d matrix were tested in order to investigate changes in wettability an d reactivity as a function ct different initial conditions, such as: ( a) chemical pretreatment of fibers by NaBH4 or HF aqueous solutions; ( b) compositional variations of the metal matrix, consisting of pure Al or Al-Cu-(Mg) alloys; and (c) different materials as system support, acting at the same time as system heating resistance. The reaction int erfaces have been observed using a scanning electron microscope equipp ed with energy dispersion and wavelength dispersion spectroscopy (EDS and WDS) analysis facilities. Some conclusions are arrived at by compa ring the present results with those obtained in a previous work based on the study of a HF-pretreated fiber/AA 6061 alloy composite.