PROTECTIVE LAYER FOR PROTECTING PARTS AGAINST CORROSION, OXIDATION AND EXCESSIVE THERMAL STRESSES, AS WELL AS PROCESS FOR PRODUCING THE SAME, PROTECTIVE LAYER FOR PROTECTING PARTS FROM CORROSION,

摘要

The present invention relates to a protective layer for protecting components from corrosion and oxidation at elevated temperatures and from excessive thermal stresses. The protective layer includes a heat insulating layer made of a ceramic material, and an adhesive layer made of a metal alloy containing rhenium. The metal alloy is one of the alloys represented by the generic term MCrA1Y. Where M is cobalt and / or nickel and Y is at least one equivalent of a metal selected from the group consisting of yttrium and / or scandium and recrystallized elements. The protective layer is characterized by a high antioxidant and corrosion resistance of the alloy, excellent thermal fatigue resistance characteristics, and an effective and lasting combination between the alloy and the ceramic thermal insulation layer. Due to the thermal insulation, there can be a significantly higher temperature on the outer surface of the protective layer than on the pure metal protective layer, without high thermal stress being applied to the part. Thus, the protective layer is particularly suitable for parts of a gas turbine exposed to overheated flue gases, such as guide blades, operating blades or heat shields.