Boron carbide is one of the hardest materials known, surpassed only by diamonds and cubic boron nitride, yet it possesses superior thermal and chemical stability when compared to either of these materials. The chemical formula in B4C’s boron carbide process allows boron atoms to migrate into the treated material converting the surface to a condition such as a iron, nickel, cobalt or chrome bride depending on the substrate alloy.
The depth of the diffusion layer is controlled by the time and temperature of the thermal conversion, and determined by the specific application. Typical depths of diffusion range from 20 to 300 microns. The migration of born atoms forms a diffused layer, converting it from its elemental state, such as iron (Fe) in common steel, to iron boride (Fe2B). The diffused layer is now converted to a ceramic, with a known hardness of 1,850 HK, to 2,200 HK.
This diffusion also results in a significant decrease in the coefficient of friction due to the high percentage of boron; about 40%. The B4C technology becomes part of the surface, eliminating bond failures or any compromises between the coating and substrate due to improper preparation, impact from high loads, thermal erosion, corrosion, thermal shock or other external factors.