METHOD FOR PROVIDING A THERMAL BARRIER COATING AND SUBSTRATE HAVING SUCH COATING

摘要

Method for providing a thermal barrier coating (5) and substrate (1). The thermal barrier coating (5) is provided on a thermally grown oxide (4) which is grown on a metallic bond coating (3) provided on said substrate (1). Adhesion between the bond coating and thermally grown oxide coating is improved by providing projections at the interface of yttria - alumina garnet (6) 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 in an inert gas atmosphere followed by controlled preoxidation.