The synthesis of single-phase β-Sialon porous ceramics using self-propagating high-temperature processing

Abstract

The target of the present research is to fabricate single-phase β-Sialon porous ceramics by self-propagating high-temperature synthesis (SHS). Samples with composition of Si6-zAlzOzN8-z (z = 0.5) were prepared by the spontaneous reaction of initial mixture of Si, Si3N4, Al, and Al2O3 at high-pressure N2 gas atmosphere. The impacts of Si content on the porosity, phase composition, microstructural morphology, and flexural strength of the fabricated materials were studied in detail. Anticipative target was achieved by adjusting Si content of initial materials and resultant reaction temperature of SHS process. Sample prepared with 35 wt% Si presented single phase of β-Sialon, homogeneous and elongated morphology, and high flexural strength of 150 MPa. To the best of our knowledge, it is the first report to synthesize single-phase β-Sialon porous ceramics by such a rapid and cheap method.