Sol-gel approach to near-net-shape oxide-oxide composites reinforced with short alumina fibres—The effect of crystallization

摘要

Near-net-shape (NNS) high alumina (aluminarsilica = 96:4, in equivalent weight ratio) fibre reinforced ceramic matrix composites (CMCs) were prepared with single and bicomponent sols following sol-gel vacuum infiltration technique. The CMCs were characterized by X-ray diffraction (XRD), three-point bend test and scanning electron microscopy (SEM). Crystallization of tetragonal zirconia (t-ZrO_2) in the composite, CZY having zirconia-yttria matrix and that of gamma alumina (gamma-Al_2O_3) in the composites, CAZ having alumina-zirconia matrix, CAS having alumina-silica matrix and CA having alumina matrix, enhanced the flexural strength values and pseudo-ductile character of CMCs.