GRAPHENE OXIDE COATED SILICON NITRIDE COMPOSITE POWDER, PREPARATION THEREFOR AND APPLICATION THEREOF, AND AL₂O₃ BASED CERAMIC CUTTER MATERIAL

摘要

A graphene oxide coated silicon nitride composite powder, a preparation therefor and application thereof, and a Al₂O₃ based ceramic cutter material. High-temperature surface oxidation is carried out on a Si₃N₄ power in hydrogen peroxide, and then a surface graft modification treatment is performed on the Si₃N₄ by using a coupling agent. Then the graphene oxide coated silicon nitride composite powder is obtained by using a graphene oxide aqueous solution to coat the graft modified Si₃N₄ particles. Further provided is an aluminium oxide-based composite ceramics cutter material added with the graphene oxide coated silicon nitride composite powder, the material being made by hot pressing and sintering the following raw materials by mass percentage: graphene oxide coated silicon nitride 5-30%, magnesium oxide 0.25-5%, molybdenum 0.5-5%, nickel 0.5-5%, and the rest material is Al₂O₃. The graphene oxide coated silicon nitride composite powder has a good coating integrity. The addition and use of the graphene oxide cladded silicon nitride composite powder into a ceramic material can obviously improve the mechanical properties of the ceramic material.