Silicon Nitride

Silicon Nitride (Si3N4) Ceramics Description

Silicon nitride (Si3N4) is a high-melting-point material with high fracture toughness and excellent thermal shock resistance. The powder of silicon nitride can be sintered to designed shape. It is considered to be one of the few monolithic ceramic materials that can withstand severe thermal shock and thermal gradient generated by hydrogen and oxygen rocket engines.

Preparation of Si3N4 ceramics includes reaction sintering, hot-pressing sintering, pressure-less sintering, and gas pressure sintering. Due to different preparation processes, each type of silicon nitride ceramic has different microstructures (such as porosity and pore morphology, grain morphology, intergranular morphology, intergranular second phase content, etc.). Gas pressure sintering is the most popular way at present.

Silicon Nitride Ceramic Properties

Color: Gray and Gray-black

Density: 3.2~3.25 g/cm3

Hardness: HRA 92~94

Highest Operating Temperature: 1300 ~1600 ℃

Thermal Conductivity: 23-25 W.(M.K)-1

Bending Strength: ≥ 900 Mpa

Fracture Toughness: 6~8 (Mpa.m1/2)

Thermal Expansion Coefficient (at 0~1400℃): 2.95~3  ×10-6/℃

Silicon Nitride Applications

Foundries

Electronics

Oil & Gas

Automotive

Aerospace

Silicon Nitride Products

*Plate, Sheets, Tube, Rod, thermocouples protecting tubes

*Bearings, bearing balls, seal rings, forming roller, electrical insulator, crucibles, and other customized parts