IN231037: A process for the preparation of silicon nitride powder

This invention relates to a process for the preparation of silicon nitride powder. The process comprises homogenizing and powdering by conventional methods a composition essentially consisting of: 44-60 weight% SiO2, 19-27 weight% C, 3.5-13 weight% p-Si3N4, and 11-26 weight% Fe(NO3)3. 9H2O, passing the powder through 100 mesh, pressing the powder so obtained by conventional methods to form green compacts, sintering the green compacts at a temperature in the range of 1475 to 1550°C in nitrogen atmosphere, grinding by conventional methods to obtain silicon nitride powder.