论文信息 - Coatings of Nb-based Alloy by Cr and/or Al Pack Cementations and Its Oxidation Behavior in Air at 1273-1473 K

Coatings of Nb-based Alloy by Cr and/or Al Pack Cementations and Its Oxidation Behavior in Air at 1273-1473 K

An Nb–5Mo–15W alloy (mass%) was surface-treated in vacuum by Cr and/or Al pack cementations, and the oxidation behavior of the coatedalloys was investigatedin air at temperatures up to 1473 K for 32.4 ks. The Al packedalloy formeda coating layer with the outer NbAl 2 andthe inner Nb 3Al, andshowedpoor oxidation resistance. The Cr packedalloy formeda coating with outer � -Cr andinner Cr 2Nb layer, and showedgoodoxidation resistance up to 1373 K. The alloy packedwith Cr andthen Al formeda coating layer with outermost � -Cr(Al), outer � Cr(Nb), andinner Cr 2Nb layers, andthis coatedalloy showedgoodoxidation resistance up to 1473 K by forming an Al 2O3 scale. (ReceivedJanuary 29, 2003; AcceptedFebruary 24, 2003)

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