Ni-BASED SINGLE CRYSTAL SUPERALLOY AND COMPONENT OBTAINED FROM THE SAME

Abstract

Provided is an Ni-based single crystal superalloy wherein the ingredients have a composition containing, as ratio by mass, from 5.0% by mass to 7.0% by mass of Al, from 4.0% by mass to 8.0% by mass of Ta, from 0% by mass to 2.0% by mass of Mo, from 3.0% by mass to 8.0% by mass of W, from 3.0% by mass to 8.0% by mass of Re, from 0% by mass to 0.50% by mass of Hf, from 3.0% by mass to 7.0% by mass of Cr, from 0% by mass to 9.9% by mass of Co and from 1.0% by mass to 10.0% by mass of Ru, with the balance of Ni and inevitable impurities. The alloy prevents TCP phase precipitation at high temperatures, therefore having improved strength at high temperatures and having oxidation resistance at high temperatures. The above-mentioned first-generation alloy CMSX-2 and second-generation alloy CMSX-4 are, though comparable thereto in point of creep strength at low temperatures, inferior to third-generation alloys in point of creep strength at high temperatures, since a large quantity of eutectic γ′-phase remains therein even after high-temperature solution treatment.

1 . An Ni-based single crystal superalloy comprising Al, Ta, W, Re, Cr and Ru as the main additive elements, wherein the ingredients have a composition containing, as ratio by mass, from 5.0% by mass to 7.0% by mass of Al, from 4.0% by mass to 8.0% by mass of Ta, from 0% by mass to 2.0% by mass of Mo, from 3.0% by mass to 8.0% by mass of W, from 3.0% by mass to 8.0% by mass of Re, from 0% by mass to 0.50% by mass of Hf, from 3.0% by mass to 7.0% by mass of Cr, from 0% by mass to 9.9% by mass of Co and from 1.0% by mass to 10.0% by mass of Ru, with the balance of Ni and inevitable impurities. 
     
     
         2 . An Ni-based single crystal superalloy comprising Al, Ta, W, Re, Cr and Ru as the main additive elements, wherein the ingredients have a composition containing, as ratio by mass, from 5.0% by mass to 7.0% by mass of Al, from 4.0% by mass to 8.0% by mass of Ta, from 0% by mass to less than 1.1% by mass of Mo, from 3.0% by mass to 8.0% by mass of W, from 3.0% by mass to 8.0% by mass of Re, from 0% by mass to 0.50% by mass of Hf, from 3.0% by mass to 7.0% by mass of Cr, from 0% by mass to 9.9% by mass of Co and from 1.0% by mass to 10.0% by mass of Ru, with the balance of Ni and inevitable impurities. 
     
     
         3 . An Ni-based single crystal superalloy comprising Al, Ta, W, Re, Cr and Ru as the main additive elements, wherein the ingredients have a composition containing, as ratio by mass, from 5.0% by mass to 7.0% by mass of Al, from 4.0% by mass to 8.0% by mass of Ta, from 0% by mass to less than 1.1% by mass of Mo, from 3.0% by mass to 5.0% by mass of W, from 3.0% by mass to 8.0% by mass of Re, from 0% by mass to 0.50% by mass of Hf, from 3.0% by mass to 7.0% by mass of Cr, from 0% by mass to 9.9% by mass of Co and from 1.0% by mass to 10.0% by mass of Ru, with the balance of Ni and inevitable impurities. 
     
     
         4 . An Ni-based single crystal superalloy comprising Al, Ta, W, Re, Cr and Ru as the main additive elements, wherein the ingredients have a composition containing, as ratio by mass, from 5.0% by mass to 7.0% by mass of Al, from 4.0% by mass to 8.0% by mass of Ta, from 0% by mass to less than 1.1% by mass of Mo, from 3.0% by mass to 5.0% by mass of W, from 3.0% by mass to 8.0% by mass of Re, from 0% by mass to less than 0.12% by mass of Hf, from 3.0% by mass to 7.0% by mass of Cr, from 0% by mass to 9.9% by mass of Co and from 1.0% by mass to 10.0% by mass of Ru, with the balance of Ni and inevitable impurities. 
     
     
         5 . An Ni-based single crystal superalloy comprising Al, Ta, W, Re, Cr and Ru as the main additive elements, wherein the ingredients have a Composition containing, as ratio by mass, from 5.0% by mass to 7.0% by mass of Al, from 4.0% by mass to 8.0% by mass of Ta, from 0% by mass to less than 1.1% by mass of Mo, from 3.0% by mass to less than 5.0% by mass of W, from 5.0% by mass to 8.0% by mass of Re, from 0% by mass to less than 0.12% by mass of Hf, from 3.0% by mass to 7.0% by mass of Cr, from 0% by mass to 9.9% by mass of Co and from 1.0% by mass to 10.0% by mass of Ru, with the balance of Ni and inevitable impurities. 
     
     
         6 . An Ni-based single crystal superalloy comprising Al, Ta, W, Re, Cr and Ru as the main additive elements, wherein the ingredients have a composition containing, as ratio by mass, from 5.0% by mass to 7.0% by mass of Al, from 4.0% by mass to 8.0% by mass of Ta, from 0% by mass to less than 1.1% by mass of Mo, from 3.0% by mass to less than 5.0% by mass of W, from 5.0% by mass to 8.0% by mass of Re, from 0% by mass to less than 0.12% by mass of Hf, from 3.0% by mass to 7.0% by mass of Cr, from 0% by mass to 9.9% by mass of Co and from 4.1% by mass to 8.0% by mass of Ru, with the balance of Ni and inevitable impurities. 
     
     
         7 . An Ni-based single crystal superalloy comprising Al, Ta, W, Re, Cr and Ru as the main additive elements, wherein the ingredients have a composition containing, as ratio by mass, from 5.0% by mass to 7.0% by mass of Al, from 4.0% by mass to 8.0% by mass of Ta, from 0.1% by mass to less than 1.1% by mass of Mo, from 3.0% by mass to less than 5.0% by mass of W, from 5.0% by mass to 8.0% by mass of Re, from 0% by mass to less than 0.12% by mass of Hf, from 3.0% by mass to 7.0% by mass of Cr, from 0% by mass to 9.9% by mass of Co and from 4.1% by mass to 8.0% by mass of Ru, with the balance of Ni and inevitable impurities. 
     
     
         8 . An Ni-based single crystal superalloy comprising Al, Ta, W, Re, Cr and Ru as the main additive elements, wherein the ingredients have a composition containing, as ratio by mass, from 5.0% by mass to 7.0% by mass of Al, from 4.0% by mass to 8.0% by mass of Ta, from 0.1% by mass to less than 1.1% by mass of Mo, from 3.0% by mass to less than 5.0% by mass of W, from 5.0% by mass to 8.0% by mass of Re, from 0% by mass to less than 0.1% by mass of Hf, from 3.0% by mass to 7.0% by mass of Cr, from 0% by mass to 9.9% by mass of Co and from 4.1% by mass to 8.0% by mass of Ru, with the balance of Ni and inevitable impurities. 
     
     
         9 . The Ni-based single crystal superalloy as claimed in  claim 1 , which further contains Ti in an amount, as ratio by mass, of at most 2.0% by mass. 
     
     
         10 . The Ni-based single crystal superalloy as claimed in  claim 1 , which further contains at least any one of B, C, Si, Y, La, Ce, V, Zr and Nb. 
     
     
         11 . The Ni-based single crystal superalloy as claimed in  claim 1 , wherein, when the lattice constant of the matrix phase is represented by a1 and the lattice constant of the precipitation phase is represented by a2, then the relation of a1 and a2 satisfies 0.990a1≦a2≦a1. 
     
     
         12 . An Ni-based single crystal superalloy component produced by the use of the Ni-based single crystal superalloy of  claim 1 .