Alloy, protective layer and component

Abstract

An alloy to a protective layer for protecting a component against corrosion and/or oxidation, in particular at high temperatures is proposed. Known protective layers with a high Cr content and in addition silicon form brittle phases which additionally embrittle during use under the influence of carbon. The proposed protective layer has the composition of from 24% to 26% cobalt, from 10% to 12% aluminum, from 0.2% to 0.5% yttrium, from 12% to 14% chromium, from 0.3% to 5.0% tantalum, nickel.

1 .- 7 . (canceled) 
     
     
         8 . An alloy, comprising (data in wt %):
 24%-26% cobalt,   12%-14% chromium,   10%-12% aluminum,   0.2%-0.5% of at least one element from the group comprising scandium and rare earth elements,   0.3%-3% tantalum, and   nickel.   
     
     
         9 . The alloy as claimed in  claim 8 , comprising:
 25% cobalt,   13% chromium,   11% aluminum   0.3% of the at least one element from the group comprising scandium and rare earth elements,   0.5%-2.0% tantalum, and   remainder nickel   
     
     
         10 . The alloy as claimed in  claim 8 , wherein the at least one element from the group comprising scandium and rare earth elements is yttrium. 
     
     
         11 . The alloy as claimed in  claim 8 , wherein the alloy does not contain rhenium. 
     
     
         12 . The alloy as claimed in  claim 8 , wherein the alloy does not contain silicon. 
     
     
         13 . The alloy as claimed in  claim 8 , wherein the alloy does not contain zirconium and/or not contain titanium and/or not contain gallium and/or not contain germanium. 
     
     
         14 . The alloy as claimed in  claim 8 , wherein the alloy consists of cobalt, chromium, aluminum, yttrium, tantalum, and nickel. 
     
     
         15 . A protective layer for protecting a component against corrosion and/or oxidation at a high temperature, comprising:
 an alloy as claimed in  claim 8 .   
     
     
         16 . The protective layer as claimed in  claim 15 , wherein the protective layer is a single layer. 
     
     
         17 . A component of a gas turbine, comprising:
 a nickel-based or cobalt-based substrate; and   a protective layer as claimed in  claim 15  for protecting against corrosion and oxidation at a high temperature.   
     
     
         18 . The component as claimed in  claim 17 , wherein the protective layer comprises only one metal protective layer, and wherein a ceramic thermal barrier layer is applied onto the protective layer.