Thermal shock resistance of chemically vapour-deposited molybdenum coatings on graphite

Article abstract of DOI:10.1016/0022-5088(89)90093-3

Thermal shock tests were performed for chemically vapour deposited molybdenum coatings on graphite to examine effects of thermal shock heating parameters and deposition conditions. The coatings were prepared at deposition temperatures ranging from 400 to 700°C using molybdenum hexacarbonyl, Mo(CO)₆, as a feed material and POCO graphite as a substrate. The surface melting limit for the coating depended on both power density and pulse duration. The coating had a constant surface melting limit expressed as Fτ ^1/2 , where F was the power density that caused surface melting during a specified pulse duration τ. The thermal shock resistance correlated with deposition conditions; the surface melting limit of the coating increased and the coatings showed more favourable thermal shock resistance as deposition temperature increased from 400 to 700°C.