Layer System

Abstract

Thermal barrier coating layer systems, in addition to good thermal barrier properties, also have to have a long service life of the thermal barrier coating. The layer system according to the invention comprises a specially adapted layer sequence of metallic bonding layer, inner ceramic layer and outer ceramic layer.

1 .- 3 . (canceled) 
   
   
       4 . A layer system adapted for use in a high temperature environment, comprising:
 a substrate;   a metallic bond layer arranged on the substrate comprising:
 24-26 wt % cobalt, 
 16-18 wt % chromium, 
 9.5-11 wt % aluminum, 
 0.3-0.5 wt % yttrium, 
 0.5-2 wt % rhenium, and 
 remainder nickel; 
   a yttrium-stabilized zirconium oxide inner ceramic layer arranged on the bond layer; and   an outer ceramic layer arranged on the inner ceramic layer comprising:
 80 wt % of a Gd 2 Zr 2 O 7  pyrochlore. 
   
   
   
       5 . The layer system as claimed in  claim 4 , wherein the layer system consists essentially of: the substrate, the metallic bond layer, the inner ceramic layer and the outer ceramic layer. 
   
   
       6 . The layer system as claimed in  claim 4 , wherein the outer ceramic layer comprises 100 wt % of the Gd 2 Zr 2 O 7  pyrochlore. 
   
   
       7 . The turbine blade or vane claimed in  claim 4 , wherein the substrate has a single crystal structure. 
   
   
       8 . A high temperature coated turbine component, comprising:
 a substrate formed from a nickel-based or cobalt-based super alloy;   a metallic bond layer arranged on the substrate comprising:
 11-13 wt % cobalt, 
 20-22 wt % chromium, 
 10.5-11.5 wt % aluminum, 
 0.3-0.5 wt % yttrium, 
 1.5-2.5 wt % rhenium, and 
 remainder nickel. 
   a yttrium-stabilized zirconium oxide inner ceramic layer arranged on the bond layer; and   an outer ceramic layer arranged on the inner ceramic layer comprising:
 80 wt % of a Gd 2 Hf 2 O 7  pyrochlore. 
   
   
   
       9 . The coated turbine component claimed in  claim 8 , wherein the coated turbine component consists essentially of: the substrate, the metallic bond layer, the inner ceramic layer and the outer ceramic layer. 
   
   
       10 . The coated turbine component claimed in  claim 8 , wherein the outer ceramic layer comprises 100 wt % of the Gd 2 Hf 2 O 7  pyrochlore. 
   
   
       11 . The turbine blade or vane claimed in  claim 8 , wherein the high temperature coated turbine component is a blade or vane. 
   
   
       12 . The coated turbine component claimed in  claim 11 , wherein the superalloy substrate has a single crystal structure. 
   
   
       13 . The coated turbine component claimed in  claim 8 , wherein the yttrium-stabilized zirconium oxide inner ceramic layer is applied via a plasma-spray or an electron beam physical vapor deposition process.