MULTILAYER COATINGS BY CONTINUOUS DETONATION SYSTEM SPRAY TECHNIQUE

Surface protection of high-temperature components for power generation has become one of the most advanced fields of modern engineering. In this area, a multilayer coating of chromium oxide/chromium carbide for erosion-corrosion protection of furnace boiler-walls has been produce d by thermal spray continuous detonation system (CDS) technique. These composite coatings present a microstructure made by alternate phases of chromium carbide cermet and oxides resulting from preferential oxid ation of chromium compounds. Mechanisms for the generation of such mix ed structure are discussed. Produced coatings have been characterized by electron probe microanalysis, X-ray diffraction and ultramicrohardn ess techniques, combined with traditional procedures of metallographic preparation, quantitative image analysis, and microhardness testing. (C) 1998 Elsevier Science S.A.