Lightweight Heat-Resistant Material for Generator Gas Turbine

Abstract

The present invention overcomes brittleness of various beryllium alloys including beryllium intermetallic compounds and thereby provides a lightweight material for gas turbines. It's achieved by employing an alloy consisting essentially of an alloy of any one or more intermetallic compounds selected from the group of Be 12 M, but Be 13 M if M is Zr, Be 10 M, and Be 17 M, where M is any one or more metallic elements selected from the group of Ti, V, Mo, W, Zr, Nb and Ta.

1 . A material for gas turbines, consisting essentially of: 
 an alloy of any one or more intermetallic compounds selected from the group of Be 12 M, but Be 13 M if M is Zr, Be 10 M, and Be 17 M 2 , where M is any one or more metallic elements selected from the group of Ti, V, Mo, W, Zr, Nb and Ta.    
   
   
       2 . The material for gas turbines as recited in  claim 1 , wherein the alloy includes a composite phase including any two or more selected from the group of Be 12 M, but Be 13 M if M is Zr, Be 10 M, and Be 17 M 2 .  
   
   
       3 . The material for gas turbines as recited in  claim 1 , wherein an average content x of M satisfies 7.7<x<10.5 (at %), but 7.1<x<10.5 (at %) if M is Zr.  
   
   
       4 . The material for gas turbines as recited in  claim 2 , wherein an average content x of M satisfies 7.7<x<10.5 (at %), but 7.1<x<10.5 (at %) if M is Zr.  
   
   
       5 . A material for gas turbines, wherein the alloy is produced by mixing, smelting, and casting one or more metals M selected from the group of Ti, V, Zr, Nb, Ta, Mo, W and Y, with Be and unavoidable impurities as a balance in a range of an average content x of M satisfying 7.7<x<10.5 (at %), but 7.1<x<10.5 (at %) if M is Zr.  
   
   
       6 . The material for gas turbines as recited in  claim 5 , wherein a homogenizing treatment and furnace cooling are accomplished after casting.  
   
   
       7 . The material for gas turbines as recited in  claim 1 , wherein the alloy is produced by casting and an average grain size of the alloy is 50 μm or less.  
   
   
       8 . The material for gas turbines as recited in  claim 7 , wherein the casting is accomplished by a unidirectional solidification.  
   
   
       9 . The material for gas turbines as recited in  claim 1 , wherein the alloy is produced by powder metallurgy and an average grain size of the material is 50 μm or less.  
   
   
       10 . The material for gas turbines as recited in  claim 5 , wherein the alloy is produced by casting and an average grain size of the alloy is 50 μm or less.  
   
   
       11 . The material for gas turbines as recited in  claim 5 , wherein the casting is accomplished by a unidirectional solidification.  
   
   
       12 . The material for gas turbines as recited in  claim 5 , wherein the alloy is produced by powder metallurgy and an average grain size of the material is 50 μm or less.  
   
   
       13 . A gas turbine rotor blade comprising the material for gas turbines as recited in  claim 1 .  
   
   
       14 . A gas turbine rotor blade comprising the material for gas turbines as recited in  claim 5.