Precipitation Hardening High Entropy Alloy and Method of Manufacturing the Same

Abstract

High-entropy alloy, particularly a precipitation hardening high entropy alloy, is provided as a component material used in electromagnetic, chemical, shipbuilding, mechanical, and other applications, a component material used in extreme environments requiring high strength and good corrosion resistance, and the like.

What is claimed is: 
     
         1 . Precipitation hardening high-entropy alloy, the high-entropy alloy comprising:
 four or more elements selected from the group consisting of more than 5 wt % to 35 wt % or less of iron (Fe), more than 5 wt % to 35 wt % or less of chromium (Cr), more than 5 wt % to 35 wt % or less of nickel (Ni), more than 5 wt % to 35 wt % or less of manganese (Mn), more than 5 wt % to 35 wt % or less of cobalt (Co), more than 5 wt % to 35 wt % or less of copper (Cu);   one or more elements of 1) and 2):   1) one or more of 0.01 wt % to 1.5 wt % of C, 0.01 wt % to 1.5 wt % of N, and 0.01 at % to 1.5 wt % of B,   2) one or more of 0.01 wt % to 5 wt % of Ti, 0.01 wt % to 3 wt % of Zr, 0.01 wt % to 5 wt % of Hf, 0.01 wt % to 5 wt % of Mo, 0.01 wt % to 5 wt % of W, 0.01 wt % to 5 wt % of Nb, 0.01 wt % to 5 wt % of V, 0.01 wt % to 5 wt % of Ta, 0.01 wt % to 5 wt % of Ag, 0.01 wt % to 5 wt % of Si, 0.01 wt % to 5 wt % of Cu, and 0.01 wt % to 5 wt % of Ge, and inevitable residual impurities;   wherein the high-entropy alloy is provided with a matrix in which precipitates are dispersed.   
     
     
         2 . The precipitation hardening high-entropy alloy of  claim 1 , wherein the precipitate is one or more of 1) and 2):
 1) one or more of carbides (M x C), nitrides (M x N), carbonitrides (M x C,N), and borides (MBx); and   2) one or more of precipitates that include one or more of Ti, Zr, Hf, Mo, W, Nb, V, Ta, Ag, Si, Cu, or Ge, and intermetallic compounds thereof.   
     
     
         3 . The precipitation hardening high-entropy alloy of  claim 1 , wherein the precipitate has the diameter of 0.5 nm to 50 nm, and the spacing between dispersed precipitates is 1 nm to 500 nm. 
     
     
         4 . A method of manufacturing a precipitation hardening high-entropy alloy, comprising the following steps:
 (a) preparing constituent materials including   four or more elements selected from the group consisting of more than 5 wt % to 35 wt % or less of Fe, more than 5 wt % to 35 wt % or less of Cr, more than 5 wt % to 35 wt % or less of Ni, more than 5 wt % to 35 wt % or less of Mn, more than 5 wt % to 35 wt % or less of Co, and more than 5 wt % to 35 wt % or less of Cu,   one or more elements of 1) and 2):   1) one or more of 0.01 wt % to 1.5 wt % of C, 0.01 wt % to 1.5 wt % of N, and 0.01 at % to 1.5 wt % of B,   2) one or more of 0.01 wt % to 5 wt % of Ti, 0.01 wt % to 3 wt % of Zr, 0.01 wt % to 5 wt % of Hf, 0.01 wt % to 5 wt % of Mo, 0.01 wt % to 5 wt % of W, 0.01 wt % to 5 wt % of Nb, 0.01 wt % to 5 wt % of V, 0.01 wt % to 5 wt % of Ta, 0.01 wt % to 5 wt % of Ag, 0.01 wt % to 5 wt % of Si, 0.01 wt % to 5 wt % of Cu, and 0.01 wt % to 5 wt % of Ge, and inevitable residual impurities;   (b) manufacturing an alloy by melting the constituent materials of step (a), having been prepared, using casting, arc melting, or powder metallurgy;   (c) homogenization heat treating the alloy, having been manufactured, at a temperature within a range of 600° C. to 1200° C.;   (d) cooling the alloy after the homogenization heat treating; and   (e) secondary heat treating the alloy by maintaining the alloy at a temperature within a range of 300° C. to 800° C. for a certain period of time after cooling step (d) and subsequently cooling the alloy.   
     
     
         5 . The method of  claim 4 , wherein the homogenization heat treating step (c) is performed for 1 hour to 48 hours. 
     
     
         6 . The method of  claim 4 , wherein the secondary heat treating step (e) is performed by maintaining the alloy at for 0.5 hour to 72 hours at temperature and cooling the alloy. 
     
     
         7 . The method of  claim 4 , wherein the secondary heating treating of step (e) is performed by maintaining the alloy at a temperature within a range of 300° C. to 800° C. with a solution treatment above 700° C.