Abstract: Substrate such as a turbine blade provided with a coating, which consists of a material that forms a sealing oxide skin on heating. This material is a ferrous metal aluminium alloy or a ferrous metal chromium alloy, wherein the oxide skin comprises aluminium oxide or chromium oxide. In order to optimise the adhesion between the skin and the coating, it is proposed that a metal from the platinum group such as platinum or palladium be added in an amount of 0.1-0.5% (m/m). It has been found that better adhesion is obtained with this method and the detrimental effects of sodium, potassium or calcium are counteracted.

Abstract: Method for providing a thermal barrier coating and substrate. The thermal barrier coating (5) is provided on a thermally grown oxide (4) which is grown on a metallic bond coating (3) provided on the substrate (1) Adhesion between the bond coating (3) and thermally grown oxide coating (4) is improved by providing projections at the interface of yttriaalumina garnet (4) compounds. Service life at relatively high temperature of the thermally grown oxide coating (4) is improved by having alumina grain (6) with relatively large size. These are obtained by pre-annealing the bond coating (3) in an inert gas atmosphere followed by controlled preoxidation.