Mechanical properties and microstructure of silicon nitride fabricated by pressureless sintering

The microstructure and mechanical properties of sintered silicon nitride ceramics were described. Fracture toughness, microhardness and bending strength were measured. The work is aimed to show that obtained material has moderately high strength, high physical properties and duplex microstructure.

I. Introduction

Silicon nitride ceramics are widely used in a large range of high temperature applications due to successful combination of properties. In particular silicon nitride has high strength, hardness, thermal stability, etc. [1]. Ceramics based on silicon nitride are often used in many areas of mechanical engineering, engine building, chemical and aviation industries.