Ni-BASED SINGLE CRYSTAL SUPERALLOY AND TURBINE BLADE

Abstract

The present invention provides a Ni-based single crystal superalloy which has the following composition by weight: 0.1 wt % or more and 9.9 wt % or less of Co, 5.1 wt % or more and 10.0 wt % or less of Cr, 1.0 wt % or more and 4.0 wt % or less of Mo, 8.1 wt % or more and 11.0 wt % or less of W, 4.0 wt % or more and 9.0 wt % or less of Ta, 5.2 wt % or more and 7.0 wt % or less of Al, 0.1 wt % or more and 2.0 wt % or less of Ti, 0.05 wt % or more and 0.3 wt % or less of Hf, 1.0 wt % or less of Nb and less than 3.0 wt % of Re with the remainder including Ni and unavoidable impurities. This Ni-based single crystal superalloy has a low Re content and also has excellent high-temperature strength, mainly creep strength.

1 . A Ni-based single crystal superalloy which has the following composition by weight: 0.1 wt % or more and 9.9 wt % or less of Co, 5.1 wt % or more and 10.0 wt % or less of Cr, 1.0 wt % or more and 4.0 wt % or less of Mo, 8.1 wt % or more and 11.0 wt % or less of W, 4.0 wt % or more and 9.0 wt % or less of Ta, 5.2 wt % or more and 7.0 wt % or less of Al, 0.1 wt % or more and 2.0 wt % or less of Ti, 0.05 wt % or more and 0.3 wt % or less of Hf, 1.0 wt % or less of Nb and less than 3.0 wt % of Re with the remainder including Ni and unavoidable impurities. 
     
     
         2 . A Ni-based single crystal superalloy according to  claim 1 , wherein the amount of Re is 2.0 wt % or less by weight. 
     
     
         3 . A Ni-based single crystal superalloy according to  claim 1 , wherein the amount of Re is 1.4 wt % or less by weight. 
     
     
         4 . A Ni-based single crystal superalloy according to  claim 1 , wherein the amount of Re is 0.8 wt % or less by weight. 
     
     
         5 . A Ni-based single crystal superalloy according to  claim 1 , which contains 6.0 wt % of Co, 7.0 wt % of Cr, 1.5 wt % of Mo, 10.0 wt % of W, 5.5 wt % of Ta, 6.0 wt % of Al, 0.1 wt % of Ti and 0.10 wt % of Hf by weight, and contains neither Nb nor Re or contains them as unavoidable impurities. 
     
     
         6 . A Ni-based single crystal superalloy according to  claim 2 , which contains 6.0 wt % of Co, 7.0 wt % of Cr, 1.5 wt % of Mo, 10.0 wt % of W, 5.5 wt % of Ta, 6.0 wt % of Al, 0.1 wt % of Ti and 0.10 wt % of Hf by weight, and contains neither Nb nor Re or contains them as unavoidable impurities. 
     
     
         7 . A Ni-based single crystal superalloy according to  claim 3 , which contains 6.0 wt % of Co, 7.0 wt % of Cr, 1.5 wt % of Mo, 10.0 wt % of W, 5.5 wt % of Ta, 6.0 wt % of Al, 0.1 wt % of Ti and 0.10 wt % of Hf by weight, and contains neither Nb nor Re or contains them as unavoidable impurities. 
     
     
         8 . A Ni-based single crystal superalloy according to  claim 4 , which contains 6.0 wt % of Co, 7.0 wt % of Cr, 1.5 wt % of Mo, 10.0 wt % of W, 5.5 wt % of Ta, 6.0 wt % of Al, 0.1 wt % of Ti and 0.10 wt % of Hf by weight, and contains neither Nb nor Re or contains them as unavoidable impurities. 
     
     
         9 . A Ni-based single crystal superalloy according to  claim 1 , which contains 8.0 wt % of Co, 7.0 wt % of Cr, 1.8 wt % of Mo, 8.2 wt % of W, 6.0 wt % of Ta, 5.2 wt % of Al, 1.6 wt % of Ti, 0.10 wt % of Hf and 0.8 wt % of Re by weight, and contains no Nb or contains it as an unavoidable impurity. 
     
     
         10 . A Ni-based single crystal superalloy according to  claim 2 , which contains 8.0 wt % of Co, 7.0 wt % of Cr, 1.8 wt % of Mo, 8.2 wt % of W, 6.0 wt % of Ta, 5.2 wt % of Al, 1.6 wt % of Ti, 0.10 wt % of Hf and 0.8 wt % of Re by weight, and contains no Nb or contains it as an unavoidable impurity. 
     
     
         11 . A Ni-based single crystal superalloy according to  claim 3 , which contains 8.0 wt % of Co, 7.0 wt % of Cr, 1.8 wt % of Mo, 8.2 wt % of W, 6.0 wt % of Ta, 5.2 wt % of Al, 1.6 wt % of Ti, 0.10 wt % of Hf and 0.8 wt % of Re by weight, and contains no Nb or contains it as an unavoidable impurity. 
     
     
         12 . A Ni-based single crystal superalloy according to  claim 4 , which contains 8.0 wt % of Co, 7.0 wt % of Cr, 1.8 wt % of Mo, 8.2 wt % of W, 6.0 wt % of Ta, 5.2 wt % of Al, 1.6 wt % of Ti, 0.10 wt % of Hf and 0.8 wt % of Re by weight, and contains no Nb or contains it as an unavoidable impurity. 
     
     
         13 . A Ni-based single crystal superalloy according to  claim 1 , which contains 8.0 wt % of Co, 6.5 wt % of Cr, 1.4 wt % of Mo, 8.1 wt % of W, 6.0 wt % of Ta, 5.8 wt % of Al, 1.0 wt % of Ti, 0.10 wt % of Hf and 1.4 wt % of Re by weight, and contains no Nb or contains it as an unavoidable impurity. 
     
     
         14 . A Ni-based single crystal superalloy according to  claim 2 , which contains 8.0 wt % of Co, 6.5 wt % of Cr, 1.4 wt % of Mo, 8.1 wt % of W, 6.0 wt % of Ta, 5.8 wt % of Al, 1.0 wt % of Ti, 0.10 wt % of Hf and 1.4 wt % of Re by weight, and contains no Nb or contains it as an unavoidable impurity. 
     
     
         15 . A Ni-based single crystal superalloy according to  claim 3 , which contains 8.0 wt % of Co, 6.5 wt % of Cr, 1.4 wt % of Mo, 8.1 wt % of W, 6.0 wt % of Ta, 5.8 wt % of Al, 1.0 wt % of Ti, 0.10 wt % of Hf and 1.4 wt % of Re by weight, and contains no Nb or contains it as an unavoidable impurity. 
     
     
         16 . A turbine blade which incorporates the Ni-based single crystal superalloy according to  claim 1 .