Turbine Blade for Industrial Gas Turbine and Industrial Gas Turbine

Abstract

A turbine blade for industrial gas turbine is used which includes a blade substrate formed of a single-crystal heat-resistant alloy containing C: 0.06 to 0.08%, B: 0.016 to 0.035%, Hf: 0.2 to 0.3%, Cr: 6.9 to 7.3%, Mo: 0.7 to 1.0%, W: 7.0 to 9.0%, Re: 1.2 to 1.6%, Ta: 8.5 to 9.5%, Nb: 0.6 to 1.0%, Al: 4.9 to 5.2%, Co: 0.8 to 1.2%, and the remainder substantially consisting of Ni with reference to mass, and includes a diffusion barrier layer, a metal layer, a bond coat, and a top coat, these layers and coats being stacked in this order on a surface of the blade substrate, the metal layer having a thickness of 5 to 30 μm. Thus, the turbine blade can be provided which has a thermal barrier coating formed without loss of a function of the diffusion barrier layer.

What is claimed is: 
     
         1 . A turbine blade for industrial gas turbine comprising:
 a blade substrate formed of a single-crystal heat-resistant alloy containing C: 0.06 to 0.08%, B: 0.016 to 0. 035%, Hf: 0.2 to 0.3%, Cr: 6.9 to 7.3%, Mo: 0.7 to 1.0%, W: 7.0 to 9.0%, Re: 1.2 to 1.6%, Ta: 8.5 to 9.5%, Nb: 0.6 to 1.0%, Al: 4.9 to 5.2%, Co: 0.8 to 1. 2%, and the remainder substantially consisting of Ni with reference to mass;   a diffusion barrier layer;   a metal layer;   a bond coat;   and a top coat,   wherein the diffusion barrier layer, the metal layer, the bond coat and the top coat are stacked in this order on a surface of the blade substrate, and the metal layer has a thickness of 5 to 30 μm.   
     
     
         2 . The turbine blade according to  claim 1 ,
 wherein the diffusion barrier layer is composed of an intermetallic compound containing Re, Cr and Ni.   
     
     
         3 . An industrial gas turbine including the turbine blade according to  claim 1 . 
     
     
         4 . A method of manufacturing the turbine blade according to  claim 1 , comprising the steps of:
 forming the diffusion barrier layer on the surface of the blade substrate;   forming the metal layer on a surface of the diffusion barrier layer;   performing a blast treatment to a surface of the metal layer; and   forming the bond coat and the top coat by a thermal spray.