Properties and applications of boron carbide ceramics

One of the characteristics of boron carbide ceramics is hard, its microhardness is about 5000mpa (50GPa), inferior to diamond (90~ 100GPa) and CBN(80 ~ 90GPa), its grinding efficiency can reach 60% ~ 70% of diamond, is 1 times of SiC, is 1~ 2 times of corundum grinding ability, It has good acid and alkali resistance and low thermal expansion coefficient (4.5x 10-6℃), so it has good thermal stability and can absorb thermal neutrons, but poor impact resistance and high brittleness.

Boron carbide resists air corrosion at 1000℃, but oxidizes easily in an oxidizing atmosphere at higher temperatures. Boron carbide has high acid and alkali resistance, and has the property of not being wetted by most molten metals, and is quite stable in contact with these substances.

Boron carbide powder can be directly used for grinding gems, bearings, etc. Boron carbide ceramics can be used as abrasive, cutting tools, parts nozzle, bearings, axles and so on. Using its good thermal conductivity, low thermal expansion coefficient, can absorb thermal neutron characteristics, can manufacture high temperature heat exchanger, nuclear reactor control agent. Using its good acid and alkali resistance, can make chemical vessels, molten metal crucible, etc.