Process for preparation of sintered silicon nitride

摘要

Disclosed is a process for preparation of a sintered silicon nitride. The process comprises the steps of: mixing a powder of silicon nitride with a powder of a sintering agent; compacting the obtained mixture; and sintering the compacted mixture in a non-oxidizing atmosphere. The feature of the process is that the powder of the sintering agent includes a powder mixture of oxide and/or hydroxide of at least two kinds of metals which has been prepared by co-precipitation. Due to the use of the co-precipitated powder as the sintering agent, it is possible to obtain a sintered silicon nitride having an excellent strength and uniformity in quality. The obtained sintered silicon nitride is preferably used as an engineering ceramic.