Process for producing spheroidized powder from feedstock materials

Abstract

Disclosed herein are embodiments of methods, devices, and assemblies for processing feedstock materials using microwave plasma processing. Specifically, the feedstock materials disclosed herein pertains to scrap materials, dehydrogenated or non-hydrogenated feed material, recycled used powder, and gas atomized powders. Microwave plasma processing can be used to spheroidize and remove contaminants. Advantageously, microwave plasma processed feedstock can be used in various applications such as additive manufacturing or powdered metallurgy (PM) applications that require high powder flowability.

1 . A spheroidized powder manufactured by a method comprising:
 introducing powder previously manufactured from a gas atomization process into a microwave plasma torch, the powder previously manufactured from a gas atomization process having an average particle size outside of a range for additive manufacturing; and   melting and spheroidizing the powder previously manufactured from a gas atomization process within the microwave plasma torch to form the spheroidized powder particles having different average particle sizes and a smaller particle size distribution from the average particles size and the particle size distribution of the powder previously manufactured from a gas atomization process.   
     
     
         2 . The spheroidized powder of  claim 1 , wherein the melting and spheroidizing increases the average particle size. 
     
     
         3 . The spheroidized powder of  claim 1 , wherein the melting and spheroidizing decreases the average particle size. 
     
     
         4 . The spheroidized powder of  claim 1 , wherein the particle size distribution of particles of the spheroidized powder is at least 50% less from 10% to 95% as compared to the particle size distribution of the powder previously manufactured from a gas atomization process. 
     
     
         5 . The spheroidized powder of  claim 1 , wherein a 50 percentile particle size of the spheroidized powder is reduced by at least 40% as compared to a 50 percentile particle size of the powder previously manufactured from a gas atomization process. 
     
     
         6 . The spheroidized powder of  claim 1 , wherein a 50 percentile particle size of the spheroidized powder is reduced by at least 50% as compared to a 50 percentile particle size of the powder previously manufactured from a gas atomization process. 
     
     
         7 . The spheroidized powder of  claim 1 , wherein a 50 percentile particle size of the spheroidized powder is increased by at least 40% as compared to a 50 percentile particle size of the powder previously manufactured from a gas atomization process. 
     
     
         8 . The spheroidized powder of  claim 1 , wherein a 50 percentile particle size of the spheroidized powder is increased by at least 50% as compared to a 50 percentile particle size of the powder previously manufactured from a gas atomization process. 
     
     
         9 . The spheroidized powder of  claim 1 , wherein the powder previously manufactured from a gas atomization process comprises a material selected from the group consisting of titanium, titanium alloy, nickel, nickel alloy, cobalt, cobalt alloy, iron, iron alloy, a ductile metal, a ductile metal alloy, and ceramic. 
     
     
         10 . A spheroidized powder comprising:
 a plurality of particles formed by introducing powder previously manufactured from a gas atomization process into a microwave plasma torch, each particle of the plurality of particles having a grain size less than 200 nanometers,   wherein the plurality of particles have a median sphericity of greater than 0.90, wherein sphericity is calculated according to the equation:   
       
         
           
             
               Sphericity 
               = 
               
                 
                   A 
                   
                     s 
                     , 
                     ideal 
                   
                 
                 
                   A 
                   
                     s 
                     , 
                     actual 
                   
                 
               
             
           
         
         
           
             wherein 
           
         
         
           
             
               
                 
                   r 
                   ideal 
                 
                 = 
                 
                   
                     
                       3 
                       ⁢ 
                       V 
                     
                     
                       4 
                       ⁢ 
                       π 
                     
                   
                   2 
                 
               
               , 
             
           
         
         
           
             
               and 
               ⁢ 
                   
               wherein 
             
           
         
         
           
             
               
                 A 
                 
                   s 
                   , 
                   ideal 
                 
               
               = 
               
                 4 
                 ⁢ 
                 π 
                 ⁢ 
                 
                   
                     r 
                     ideal 
                     2 
                   
                   . 
                 
               
             
           
         
       
     
     
         11 . The spheroidized powder of  claim 10 , wherein the plurality of particles have a median sphericity of greater than 0.95. 
     
     
         12 . The spheroidized powder of  claim 10 , wherein the plurality of particles have a median sphericity of greater than 0.99. 
     
     
         13 . The spheroidized powder of  claim 10 , wherein the plurality of particles comprise a material selected from the group consisting of titanium, titanium alloy, nickel, nickel alloy, cobalt, cobalt alloy, iron, iron alloy, a ductile metal, a ductile metal alloy, and ceramic. 
     
     
         14 . The spheroidized powder of  claim 10 , wherein the plurality of particles comprise titanium. 
     
     
         15 . The spheroidized powder of  claim 10 , wherein the plurality of particles comprise titanium alloy. 
     
     
         16 . The spheroidized powder of  claim 15 , wherein the plurality of particles comprise TiAl or Ti-64. 
     
     
         17 . The spheroidized powder of  claim 10 , wherein the plurality of particles comprise nickel. 
     
     
         18 . The spheroidized powder of  claim 17 , wherein the plurality of particles comprise Iconel  718  or Iconel  625 . 
     
     
         19 . The spheroidized powder of  claim 10 , wherein the plurality of particles comprise an oxygen content of less than about 2% by weight. 
     
     
         20 . The spheroidized powder of  claim 10 , wherein the plurality of particles comprise a particle size distribution between 15 μm to 63 μm.