SOME PROPERTIES OF PLATINUM AND PALLADIUM MODIFIED ALUMINIDE COATINGS DEPOSITED BY CVD METHOD ON NICKEL-BASE SUPERALLOYS

摘要

In the paper some functional properties (hardness and oxidation resistance) of platinum and palladium modified aluminide coatings deposited by the CVD method on a nickel-based supcralloy were determined. The platinum and palladium microlaycrs, 3 ìm thick were deposited by electroplating process. The heat treatment of electroplating microlayers was performed for 2h at the temperature 1050°C in an argon atmosphere as to increase adhesion between the coaling and the substrate. The low activity CVD aluminizing process of platinum heat treated coatings 3 ìm thick at the 1050°C for 8h using lonBond equipment was performed. The effects of aluminizing process were verified by the use of an optical microscope (microstructure and coating thickness); a scanning electron microscope and an energy dispersive spectroscope (chemical composition of the surface and cross-section of the modified aluminide coating). The hardness measurements on the cross-section of nonmodified and platinum or palladium modified aluminide coatings were performed.