Silicon Nitride

Name:
Silicon Nitride
Detailed information:

M Formula:	Si3N4
Properties:
Gray, amorphous powder (can be prepared as crystals). Sublimes at 1900C, d 3.44, bulk d 70–75 lb/cu ft depending on mesh, Mohs hardness 9+, thermal conductivity 10.83 Btu/in/sq ft/hr/F (400–2400F). Resistant to oxidation, various corrosive media, molten aluminum, zinc, lead, and tin; soluble in hydrogen fluoride.
Derivation:
Reaction of powdered silicon and nitrogen in an electric furnace at 1300C.
Use:
Refractory coatings, bonding silicon carbide, mortars, abrasives, thermocouple tubes in molten aluminum, crucibles for zone-refining germanium, rocket nozzles, high-strength fibers and whiskers, insulator and passivating agent in transistors and other solid-state devices.