Reaction interfaces of Nicalon fiber/aluminum composite systems: The influence of fiber pretreatments and matrix composition

Systems composed of Nicalon NL-202 multifilament fibers and an Al-based matrix were tested in order to investigate changes in wettability and 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 interfaces have been observed using a scanning electron microscope equipped with energy dispersion and wavelength dispersion spectroscopy (EDS and WDS) analysis facilities. Some conclusions are arrived at by comparing the present results with those obtained in a previous work based on the study of a HF-pretreated fiber/AA 6061 alloy composite.