Gas turbine part provided with a protective coating, and a method of making a protective coating on a superalloy metal substrate

摘要

A gas turbine part comprises a superalloy metal substrate, a bonding underlayer formed on the substrate and comprising an intermetallic compound of aluminum, nickel, and platinum, and a ceramic outer layer anchored on the alumina film formed on the bonding underlayer. The bonding underlayer essentially comprises an Ni—Pt—Al ternary system constituted by an aluminum-enriched α-NiPt type structure, in particular an Ni—Pt—Al ternary system having a composition Ni_zPt_yAl_x in which z, y, and x are such that 0.05≦z≦0.40, 0.30≦y≦0.60, and 0.15≦x≦0.40.