High Quality Spherical Powders for Additive Manufacturing Processes Along With Methods of Their Formation

Abstract

Methods for forming a high-quality powder from a feedstock powder of feedstock particles having irregular shapes are provided. The method includes exposing the feedstock powder to a plasma field to form a treated powder of treated particles having a more spherical shape than the feedstock particles. Prior to the plasma field exposure, the feedstock particles have an oxidized layer thereon as a result from previous exposure to water. After exposure to the plasma field, the treated particles are substantially free from an oxidized layer.

What is claimed is: 
     
         1 . A method of forming a high-quality powder from a feedstock powder of feedstock particles having irregular shapes, the method comprising:
 exposing the feedstock powder to a plasma field to form a treated powder of treated particles having a more spherical shape than the feedstock particles, wherein the feedstock particles have an oxidized layer thereon as a result from previous exposure to water, and wherein the treated particles are substantially free from an oxidized layer.   
     
     
         2 . The method of  claim 1 , wherein the feedstock powder is formed from water atomization, mechanical crushing or grinding, gas atomization, and/or plasma atomization. 
     
     
         3 . The method of  claim 1 , wherein the oxidized layer on the feedstock particles is a result of exposure to water during a water atomization process that formed the feedstock particles. 
     
     
         4 . The method of  claim 1 , wherein exposing the feedstock powder to the plasma field comprises:
 introducing the feedstock powder into the plasma field such that at least a portion the surface of the feedstock particles melts or evaporates to form the more spherical shape.   
     
     
         5 . The method of  claim 4 , wherein the plasma field comprises a reducing component that reacts with the oxidized layer on the feedstock particles. 
     
     
         6 . The method of  claim 5 , wherein the reducing component comprises hydrogen, carbon monoxide, or a mixture thereof. 
     
     
         7 . The method of  claim 1 , wherein the feedstock particles have a maximum size of about 150 μm. 
     
     
         8 . The method of  claim 7 , wherein the feedstock particles have an average size of about 10 μm to about 150 μm. 
     
     
         9 . The method of  claim 8 , wherein the feedstock particles have an average size of about 50 μm to about 100 μm. 
     
     
         10 . The method of  claim 1 , wherein the treated particles have an average particle size that is less than an average particle size of the feedstock particles. 
     
     
         11 . The method of  claim 1 , wherein the treated particles have an average particle size that is about 10% to about 90% of the average particle size of the feedstock particles. 
     
     
         12 . The method of  claim 1 , wherein the feedstock particles comprise a metal material. 
     
     
         13 . The method of  claim 12 , wherein the metal material comprises a pure metal, an iron alloy, an aluminum alloy, a nickel alloy, a chrome alloy, a nickel-based superalloy, an iron-based superalloy, a cobalt-based superalloy, or a mixture thereof. 
     
     
         14 . The method of  claim 1 , wherein carbon particles are mixed with the feedstock particles within the plasma field. 
     
     
         15 . The treated powder comprising the treated particles formed from the method of  claim 1 . 
     
     
         16 . A method of additively manufacturing a component from the treated powder of  claim 15 . 
     
     
         17 . A method of forming a high-quality powder, the method comprising:
 forming a feedstock powder via water atomization, wherein the feedstock powder includes feedstock particles having irregular shapes, and wherein the feedstock particles have an oxidized layer thereon;   thereafter, exposing the feedstock powder to a plasma field to melt or evaporate at least a portion of the surface of the feedstock particles such that a treated powder of treated particles is formed having a more spherical shape than the feedstock particles, wherein the plasma field comprises a reducing component that reacts with the oxidized layer on the feedstock particles such that the treated particles are substantially free from an oxidized layer.   
     
     
         18 . The method of  claim 17 , wherein the reducing component comprises hydrogen, carbon monoxide, or a mixture thereof. 
     
     
         19 . The method of  claim 17 , wherein the treated particles have an average particle size that is less than an average particle size of the feedstock particles. 
     
     
         20 . The method of  claim 1 , wherein the feedstock particles comprise a metal material, and wherein carbon particles are mixed with the feedstock particles within the plasma field.