AbstractThe high cost and lengthy preparation time of conventional ceramic bend-bar strength specimens is holding back the development of sintered silicon nitride ceramics having good high–temperature properties. The equipment now available for high–temperature sintering enables discs of high–strength sintered silicon nitride to be fabricated in a wide range of formulations. The use of disc specimens has led to a considerable increase in the rate and volume of research into mechanical properties and behaviour in a high-temperature environment. This research has demonstrated the value of using disc specimens to reduce the time and cost of programmes for developing materials suitable for gas-turbine and other demanding applications.MST/232