The effect of precursor composition and sintering additives on the formation of β-sialon from Al, Si and Al2O3 powders

Abstract

This version is available at https://strathprints.strath.ac.uk/30842/ Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Please check the manuscript for details of any other licences that may have been applied. You may not engage in further distribution of the material for any profitmaking activities or any commercial gain. You may freely distribute both the url (https://strathprints.strath.ac.uk/) and the content of this paper for research or private study, educational, or not-for-profit purposes without prior permission or charge.Any correspondence concerning this service should be sent to the Strathprints administrator: strathprints@strath.ac.ukThe Strathprints institutional repository (https://strathprints.strath.ac.uk) is a digital archive of University of Strathclyde research outputs. It has been developed to disseminate open access research outputs, expose data about those outputs, and enable the management and persistent access to Strathclyde's intellectual output.

In-situ synthesis mechanism of plate-shaped β-Sialon and its effect on Al2O3–C refractory properties

“…1. Ewing and Yang [17] reported that 15R polytype Sialon appeared when whiskers could be formed at different temperatures, and the increase of the sintering temperature resulted in the higher yield and larger diameter of the SiC whisker. The growth mechanism of the SiC whiskers followed VS (vapor-solid) or VLS (vapor-liquid-solid) model [19][20][21].…”

Ultrafine‐grained β‐Sialon fabricated by two‐stage sintering and study on diffusion toughening of Ti–22Al–25Nb

“…[11][12][13][14] They have the same liquid-phase sintering mechanism: The sintering additives react with SiO 2 on the surface of the Si 3 N 4 particles to generate a low-eutectic-point liquid phase that wets the solid phase and thus accelerates the particle rearrangement and solid-phase dissolution-precipitation and promotes the densification of the Sialon ceramics. 15,16 However, under the action of the above sintering additives, the densification and toughening of Sialon ceramics are synchronized, and the hierarchical control cannot be realized. In this regard, how to realize the phased control of sintering aids in the densification and toughening of Sialon ceramics is the current research difficulty.…”

“…At present, the universally applied sintering additives are mainly single inorganic additives (such as MgO, Al 2 O 3 , and Y 2 O 3 ) 8–10 or composite sintering additives (such as Al 2 O 3 –Y 2 O 3 and Re 2 O 3 –MgO) 11–14 . They have the same liquid‐phase sintering mechanism: The sintering additives react with SiO 2 on the surface of the Si 3 N 4 particles to generate a low‐eutectic‐point liquid phase that wets the solid phase and thus accelerates the particle rearrangement and solid‐phase dissolution–precipitation and promotes the densification of the Sialon ceramics 15,16 . However, under the action of the above sintering additives, the densification and toughening of Sialon ceramics are synchronized, and the hierarchical control cannot be realized.…”

In‐situ synthesis of 15R‐Sialon from Al‐Si3N4‐Al2O3 composite at 1500°C via liquid‐phase sintering

“…In order to improve performance, it is preferred that the introduced metal can further transform into 15R-Sialon. Due to the difficulty of nitridation of Si and Al to Sialon, 23 the direct addition of Al and Si may not be a good choice. Relevant studies have found that Si 3 N 4 will react with Al to Si and AlN, 24,25 which can provide solid nitrogen source and liquid metal phase for the synthesis of 15R-Sialon.…”