US2025313924A1PendingUtilityA1

Medium entropy alloys and methods of preparing the same

Assignee: POSTECH RES & BUSINESS DEV FOUNDPriority: Apr 4, 2024Filed: Apr 1, 2025Published: Oct 9, 2025
Est. expiryApr 4, 2044(~17.7 yrs left)· nominal 20-yr term from priority
B22F 1/09C22C 1/047C22F 1/057C22F 1/053C22C 21/18C22C 21/10C22C 30/02C22C 30/06C22F 1/002C22F 1/16B22D 21/00
56
PatentIndex Score
0
Cited by
0
References
0
Claims

Abstract

An embodiment of the present invention provides a medium entropy alloy including an Al-rich FCC phase, a Zn-rich HCP phase, and an intermetallic compound, wherein the Al-rich FCC phase, the Zn-rich HCP phase, and the intermetallic compound include Al, Zn, and Cu, and the intermetallic compound satisfies the following equation 1. 1 ⁢ 9 ⁢ 3 ≤ ( A × B ) / C ≤ 2 ⁢ 4 ⁢ 0 [ Equation ⁢ 1 ] (In Equation 1, A represents the atom % of Al in the intermetallic compound, B represents the atom % of Cu in the intermetallic compound, and C represents the atom % of Zn in the intermetallic compound.)

Claims

exact text as granted — not AI-modified
What is claimed is: 
     
         1 . A medium entropy alloy comprising:
 an Al-rich FCC phase, a Zn-rich HCP phase and an intermetallic compound,   the Al-rich FCC phase, the Zn-rich HCP phase and the intermetallic compound comprise Al, Zn and Cu, and   the intermetallic compound satisfies the following equation 1:   
       
         
           
             
               
                 
                   
                     
                       1 
                       ⁢ 
                       9 
                       ⁢ 
                       3 
                     
                     ≤ 
                     
                       
                         ( 
                         
                           A 
                           × 
                           B 
                         
                         ) 
                       
                       / 
                       C 
                     
                     ≤ 
                     
                       2 
                       ⁢ 
                       4 
                       ⁢ 
                       0 
                     
                   
                 
                 
                   
                     [ 
                     
                       Equation 
                       ⁢ 
                          
                       1 
                     
                     ] 
                   
                 
               
             
           
         
         (In Equation 1, A represents the atom % of Al in the intermetallic compound, B represents the atom % of Cu in the intermetallic compound, and C represents the atom % of Zn in the intermetallic compound.) 
       
     
     
         2 . The medium entropy alloy of  claim 1 , wherein:
 the medium entropy alloy satisfies the following equation:   
       
         
           
             
               
                 
                   
                     0.14 
                     ≤ 
                     
                       
                         ( 
                         
                           a 
                           ⁢ 
                               
                           first 
                           ⁢ 
                               
                           peak 
                           × 
                           a 
                           ⁢ 
                               
                           fourth 
                           ⁢ 
                               
                           peak 
                         
                         ) 
                       
                       / 
                       a 
                       ⁢ 
                           
                       fifth 
                       ⁢ 
                           
                       peak 
                     
                     ≤ 
                     0.33 
                   
                 
                 
                   
                     [ 
                     
                       Equation 
                       ⁢ 
                          
                       2 
                     
                     ] 
                   
                 
               
             
           
         
         (In Equation 2, the first peak is the peak intensity when 2θ is 36±5°, the fourth peak is the peak intensity when 2θ is 65±5°, and the fifth peak is the peak intensity when 2θ is 78±5°, in the X-ray diffraction analysis (XRD) spectrum.) 
       
     
     
         3 . The medium entropy alloy of  claim 1 , wherein:
 with atom % as reference, the ratio of Zn to Al is 0.8 to 1.2.   
     
     
         4 . The medium entropy alloy of  claim 1 , wherein:
 with atom % as reference, the ratio of Cu to Al is 0.2 to 1.0.   
     
     
         5 . The medium entropy alloy of  claim 1 , wherein:
 the medium entropy alloy comprises Al: 33.3 to 45.0%, Zn: 33.3 to 45.0%, Cu: 10 to 33.3% and other impurities in atom %.   
     
     
         6 . The medium entropy alloy of  claim 1 , wherein:
 the medium entropy alloy comprises a triple phase,   wherein, the triple phase includes a first phase with Al as a primary component; a second phase with Zn as a primary component; and a third phase with Al-based intermetallic compounds and Cu-rich.   
     
     
         7 . The medium entropy alloy of  claim 6 , wherein:
 the first phase includes Al-rich FCC phase.   
     
     
         8 . The medium entropy alloy of  claim 6 , wherein:
 the second phase includes a Zn-rich HCP phase.   
     
     
         9 . The medium entropy alloy of  claim 6 , wherein:
 a composition of the first phase, based on the entire mole number of the first phase as a reference, includes Al: 45 to 60%, Zn: 35 to 50%, Cu: 5 to 10% and impurity of the balance in atom %.   
     
     
         10 . The medium entropy alloy of  claim 6 , wherein:
 a composition of the second phase,, based on the entire mole number of the second phase as a reference, includes Al: 5 to 20%, Zn: 65 to 80%, Cu: 10 to 25% and impurity of the balance in atom %.   
     
     
         11 . The medium entropy alloy of  claim 6 , wherein:
 a composition of the third phase, based on the entire mole number of the third phase as a reference, includes Al: 40 to 55%, Zn: 5 to 20%, Cu: 35 to 50% in atom %, and inevitable impurity.   
     
     
         12 . The medium entropy alloy of  claim 6 , wherein:
 the Al based intermetallic compound includes AlCu and Al 2 Cu.   
     
     
         13 . The medium entropy alloy of  claim 1 , wherein:
 a yield strength of the medium entropy alloy at room temperature 298K is 350 to 380 MPa.   
     
     
         14 . The medium entropy alloy of  claim 1 , wherein:
 a tensile strength of the medium entropy alloy at room temperature 298K is 405 to 470 Mpa.   
     
     
         15 . The medium entropy alloy of  claim 1 , wherein:
 an elongation of the medium entropy alloy at room temperature 298K is 1.2 to 5.0%.   
     
     
         16 . The medium entropy alloy of  claim 1 , wherein:
 the Al and Zn satisfy the following Equation 3.   
       
         
           
             
               
                 
                   
                     
                       [ 
                       Al 
                       ] 
                     
                     = 
                     
                       [ 
                       Zn 
                       ] 
                     
                   
                 
                 
                   
                     [ 
                     
                       Equation 
                       ⁢ 
                          
                       3 
                     
                     ] 
                   
                 
               
             
           
         
         (Here, [X] means atom % of X) 
       
     
     
         17 . A method of manufacturing a medium entropy alloy, comprising:
 manufacturing an ingot by casting a mixed powder containing Al, Zn, and Cu;   quenching the ingot;   processing the quenched ingot with severe plastic deformation (SPD); and   post-heat treatment for 2 to 50 minutes.   
     
     
         18 . The method of  claim 17 , wherein:
 the severe plastic deformation process includes the High-Pressure Torsion (HPT) process or Equal Channel Angular Pressing (ECAP) process.   
     
     
         19 . The method of  claim 18 , wherein:
 a load applied during the High-Pressure Torsion (HPT) process is 38 to 50 tons; and   5 an overall rotation speed is 5 to 40 times.   
     
     
         20 . The method of  claim 17 , wherein:
 the heat treatment temperature of the post heat treatment step is 250 to 350° C.

Join the waitlist — get patent alerts

Track US2025313924A1 — get alerts on status changes and closely related new filings.

We store only your email — no account needed. See our privacy policy.