Mechanically alloyed powder feedstock

Abstract

Disclosed herein are embodiments of mechanically alloyed powder feedstock and methods for spheroidizing them using microwave plasma processing. The spheroidized powder can be used in metal injection molding processes, hot isostatic processing, and additive manufacturing. In some embodiments, mechanical milling, such as ball milling, can be used to prepare high entropy alloys for microwave plasma processing.

1 . (canceled) 
     
     
         2 . A spheroidized powder prepared by a method comprising:
 introducing a mechanically alloyed feedstock into a microwave plasma torch, a plasma plume of the microwave plasma torch, and/or an exhaust of the microwave plasma torch, the mechanically alloyed feedstock prepared by milling a plurality of elemental powders or pre-alloyed powders; and   contacting the mechanically alloyed feedstock with a plasma within the microwave plasma torch, the plasma plume of the microwave plasma torch, and/or the exhaust of the microwave plasma torch to form spheroidized powder,   wherein the spheroidized powder comprises a high entropy alloy (HEA), and   wherein the mechanically alloyed feedstock comprises TiZrNbTaFe, AlFeVSi, FeCoNiCrTi, FeCoNiCrAl, or FeCoNiCrCu.   
     
     
         3 . The spheroidized powder of  claim 2 , wherein the mechanically alloyed feedstock is milled by ball milling. 
     
     
         4 . The spheroidized powder of  claim 2 , wherein the mechanically alloyed feedstock comprises a microstructure, and wherein the spheroidized powder maintains the microstructure. 
     
     
         5 . The spheroidized powder of  claim 2 , further comprising varying one or more of the following parameters after introducing the mechanically alloyed feedstock into the microwave plasma torch, the plasma plume of the microwave plasma torch, and/or the exhaust of the microwave plasma torch: microwave power, plasma gas flow, gas type, plasma plume length, plasma plume diameter, plasma jet velocity, exhaust chamber pressure, quench gas type, exhaust gas velocity, feedstock velocity, feed gas flow, and feedstock feed rate. 
     
     
         6 . The spheroidized powder of  claim 2 , wherein the plurality of elemental powders or pre-alloyed powders are mechanically milled for between about 1 hour and about 17 hours. 
     
     
         7 . The spheroidized powder of  claim 2 , wherein the mechanically alloyed feedstock comprises a high entropy alloy. 
     
     
         8 . The spheroidized powder of  claim 2 , wherein the mechanically alloyed feedstock comprises a non-equiatomic high entropy alloy. 
     
     
         9 . The spheroidized powder of  claim 2 , wherein the spheroidized powder comprises a sphericity greater than 0.5. 
     
     
         10 . The spheroidized powder of  claim 2 , wherein the spheroidized powder comprises a sphericity greater than 0.75. 
     
     
         11 . The spheroidized powder of  claim 2 , wherein the spheroidized powder comprises a sphericity greater than 0.9. 
     
     
         12 . The spheroidized powder of  claim 2 , wherein the spheroidized powder comprises a sphericity greater than 0.99. 
     
     
         13 . A spheroidized alloy powder prepared by a method comprising:
 introducing a mechanically alloyed feedstock into a microwave plasma torch, a plasma plume of the microwave plasma torch, and/or an exhaust of the microwave plasma torch, the mechanically alloyed feedstock prepared by milling one or more powders to form an alloy; and   contacting the mechanically alloyed feedstock with a plasma within the microwave plasma torch, the plasma plume of the microwave plasma torch, and/or the exhaust of the microwave plasma torch to form spheroidized powder,   wherein the spheroidized powder comprises an entropy of mixing of greater than about 1.67R, and   wherein the mechanically alloyed feedstock comprises TiZrNbTaFe, AlFeVSi, FeCoNiCrTi, FeCoNiCrAl, or FeCoNiCrCu.   
     
     
         14 . The spheroidized alloy powder of  claim 13 , wherein the mechanically alloyed feedstock is mechanically milled by ball milling. 
     
     
         15 . The spheroidized alloy powder of  claim 13 , wherein the alloy comprises a non-equiatomic high entropy alloy. 
     
     
         16 . The spheroidized alloy powder of  claim 13 , further comprising varying one or more of the following parameters after introducing the mechanically alloyed feedstock into the microwave plasma torch, the plasma plume of the microwave plasma torch, and/or the exhaust of the microwave plasma torch: microwave power, plasma gas flow, gas type, plasma plume length, plasma plume diameter, plasma jet velocity, exhaust chamber pressure, quench gas type, exhaust gas velocity, feedstock velocity, feed gas flow, and feedstock feed rate. 
     
     
         17 . The spheroidized alloy powder of  claim 13 , wherein the one or more powders are mechanically milled for between about 1 hour and about 17 hours. 
     
     
         18 . The spheroidized alloy powder of  claim 13 , wherein the spheroidized powder comprises a sphericity greater than 0.5. 
     
     
         19 . The spheroidized alloy powder of  claim 13 , wherein the spheroidized powder comprises a sphericity greater than 0.75. 
     
     
         20 . The spheroidized alloy powder of  claim 13 , wherein the spheroidized powder comprises a sphericity greater than 0.9. 
     
     
         21 . The spheroidized alloy powder of  claim 13 , wherein the spheroidized powder comprises a sphericity greater than 0.99.