Processing of ceramic materials

摘要

A process for treating a nitride-containing ceramic material which includes (1) comminuting the material to produce a particulate ceramic material having a particle size distribution such that at least 40% by weight of the particles have an equivalent spherical diameter (esd) smaller than 2 mu m; and (2) a ferrosilicon separation step comprising one or both of the following steps: a) subjecting the particulate ceramic material produced in step 1 to differential sedimentation in a liquid medium to produce substantial separation of a light fraction from a heavy fraction, ferrosilicon required to be separated being included in the heavy fraction and refined particulate ceramic material being included in the light fraction; b) subjecting a suspension of the particulate ceramic material to magnetic separation to produce substantial separation of magnetic particulate material from non-magnetic particulate material, refined particulate ceramic material being included in the non-magnetic material.