Chemical Properties and Oxidation of Boron Carbide

Boron carbide in air is immediately, i.e., within seconds, coated by a B2O3 layer, in presence of water by a hydroboric acid layer [172,229]. Oxidation starts at 500-600°C and accelerates significantly above 800-1000°C, depending on the humidity. The weight gain of boron carbide powder being surface-cleaned in glove boxes of 1 ppm O2 and 1 ppm H2O and subsequently Si-sputtered, Ar ion implanted, or 

Ar-implanted materials at room temperature is attributed to the enlarged surface area as well as due to the formation of structural defects which aid oxygen diffusion. 

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