High-melting superalloy and method of producing the same

Abstract

A high-melting superalloy made of iridium or rhodium or both thereof as a base and containing at least nickel together with at least one a metal selected from the metal group consisting of titanium, zirconium, hafnium, vanadium, niobium, and tantalum, wherein at least both phases of an fcc phase and an LI 2 phase are formed in the texture, and an amount of the LI 2 phase from 20 to 80% by volume.

What is claimed is:  
     
         1 . A high-melting superalloy comprising (A) from 5 to 65 atomic % of nickel and (B) from 5 to 20 atomic % of at least one metal selected from the group consisting of titanium, zirconium, hafnium, vanadium, niobium, and tantalum, with (C) from 30 to 75 atomic % of iridium or rhodium, or a mixture thereof, wherein a LI 2  phase precipitated in a fcc phase of the matrix phase, and an amount of the LI 2  phase is from 20 to 80% by volume.  
     
     
         2 . The high-melting superalloy according to  claim 1 , wherein an atomic % of sum of (A) and (B) is from 20 to 70%.  
     
     
         3 . The high-melting superalloy according to  claim 1  or  2 , wherein, in case that the metal (c) is iridium, an atomic ratio of (A) to (B) is from 0.3:1 to 8:1.  
     
     
         4 . The high-melting superalloy according to  claim 1  or  2 , wherein, in case that the metal (c) is rhodium the atomic ratio of (A) to (B) is from 0.25:1 to 12:1.  
     
     
         5 . The high-melting superalloy comprising (A) from 4 to 86 atomic % of nickel, (B) from 0.5 to 20 atomic % of at least one metal selected from the group consisting of titanium, Zirconium, hafnium, vanadium, niobium, and tantalum, and (C) from 4 to 86 atomic % of iridium or rhodium, or a mixture thereof, with (D) from 0.4 to 20 atomic % of alminum, wherein a LI 2 , phase is precipitated in a fcc phase of the matrix phase, and an amount of the LI 2 , phase is from 20 to 80% by volume.  
     
     
         6 . The high-melting superalloy according to  claim 5 , wherein the sum of atomic % of (A) and (C), and (B) and (D) are set as follows, 
       ( A )+( C )≧75 atomic %( B )+( C )≦25 atomic % 
     
     
         7 . A method of producing a high-melting superalloy as set forth in any of  claims 1  to  4 , which comprises compounding at least one of an iridium-base superalloy made of iridium as a base added with at least one metal selected from the metal group consisting of titanium, zirconium, hafnium, vanadium, niobium, and tantalum and a rhodium-base superalloy made of rhodium as a base added with at least one metal selected from the above-described metal group, with nickel, followed by ingoting to produce a high-melting superalloy.  
     
     
         8 . A method of producing a high-melting superalloy as set forth in any of  claims 1  to  6 , which comprises compounding at least one of an iridium-base superalloy made of iridium as a base added with at least one metal selected from the metal group consisting of titanium, zirconium, hafnium, vanadium, niobium, and tantalum and a rhodium-base superalloy made of rhodium as a base added with at least one metal selected from the above-described metal group, with a nickel-base alloy made of nickel as a base added with at least one metal selected from the above-described metal group, or aluminum, followed by ingoting to produce a high-melting superalloy.