Influence of a Mo interlayer on the oxidation behavior of a Cr coating on a Zr alloy substrate

Cr-based coatings with or without a Mo interlayer were deposited on a Zr substrate by multi-arc ion plating, and the effect of the Mo interlayer on the oxidation behavior of the coatings at different time lengths (maximum 90 min) at 1160 degrees C was investigated. Atomic scale characterization confirms that, on the one hand, the Mo inter-layer prevents the Cr coating from reacting with the Zr substrate to form the ZrCr2 Laves phase and, on the other hand, the solid solution structure generated due to Mo doping effectively guarantees the integrity of the Cr2O3 oxide layer and the residual Cr coating.