Silicon nitride is a highly advanced ceramic made of silicon and nitrogen atoms bonded together, with the chemical formula Si3N4. This stuff displays some really impressive strengths and capabilities that make it useful for applications where you need to withstand intense heat, pressure, and wear over long periods. Some key properties of silicon nitride include:
Extremely high hardness and wear resistance
High strength at both low and high temperatures up to 1000°C
Good thermal shock resistance
Good chemical resistance and oxidation resistance
Low thermal expansion Electrically insulating