Particulate strengthened alloy articles and methods of forming

Abstract

An article and a method for forming the article are presented. The article includes a material comprising a metal matrix and a first population of particulate phases disposed macroscopically non-uniformly within the matrix. The particulate phases include an oxide phase. Further embodiments include articles, such as turbomachinery components, fasteners, and pipes, for example, and methods for forming the articles.

1 . An article, comprising:
 a material comprising a metal matrix and a first population of particulate phases disposed macroscopically non-uniformly within the matrix, the particulate phases comprising an oxide phase.   
     
     
         2 . The article of  claim 1 , wherein the matrix comprises nickel, iron, chromium, aluminum, cobalt, titanium, or a combination thereof. 
     
     
         3 . The article of  claim 1 , wherein the matrix comprises iron and chromium. 
     
     
         4 . The article of  claim 1 , wherein the oxide phase comprises aluminum, yttrium, magnesium, molybdenum, zirconium, silicon, titanium, hafnium, tungsten, tantalum, or a combination thereof. 
     
     
         5 . The article of  claim 1 , wherein the oxide phase comprises titanium and yttrium. 
     
     
         6 . The article of  claim 1 , wherein the first population of particulate phases has a median size less than about 20 nm. 
     
     
         7 . The article of  claim 1 , wherein the first population of particulate phases has a median size less than about 10 nanometers. 
     
     
         8 . The article of  claim 1 , further comprising a second population of particulate phases disposed within the matrix, wherein the second population of particulate phases has a different size distribution from the size distribution of the first population of particulate phases. 
     
     
         9 . The article of  claim 8 , wherein the second population of particulate phases is distributed macroscopically non-uniformly within the matrix. 
     
     
         10 . The article of  claim 8 , wherein the second population of particulate phases comprises an intermetallic compound. 
     
     
         11 . The article of  claim 8 , wherein the second population of particulate phases comprises an oxide, a boride, a carbide, a nitride, or combinations thereof. 
     
     
         12 . The article of  claim 8 , wherein the second population of particulate phases has a median size in a range from about 25 nm to about 10 microns. 
     
     
         13 . The article of  claim 1 , wherein a first concentration of the first population of the particulate phases in a first region of the article is not equal to a second concentration of the first population of the particulate phases in a second region of the article, and wherein each of the first concentration and second concentration is independently within a range from about 0.1 volume percent to about 5 volume percent. 
     
     
         14 . The article of  claim 13 , wherein at least one intermediate region is disposed between the first region and the second region, and wherein the concentration of the first population of the particulate phases in the at least one intermediate region has a value that is between the first concentration and the second concentration. 
     
     
         15 . The article of  claim 13 , wherein the article is a turbomachinery component, a fastener or a pipe. 
     
     
         16 . The article of  claim 15 , wherein the article is a wheel or a spacer. 
     
     
         17 . The article of  claim 16 , wherein a first region comprises an inner surface of the wheel or spacer, and a second region comprises an outer surface of the wheel or spacer, and wherein a first concentration of the first population of the particulate phases at the inner surface is less than a second concentration of the first population of the particulate phases at the outer surface. 
     
     
         18 . The article of  claim 17 , wherein the first concentration is in a range from about 0.1 volume percent to about 2 volume percent, and the second concentration is in a range from about 0.7 volume percent to about 3 volume percent. 
     
     
         19 . A turbomachinery component, comprising:
 a radially symmetrical body comprising an inner surface proximate to a center of the body and an outer surface distal to the center of the body;   wherein the body comprises
 a material comprising
 a metal matrix, the matrix comprising iron and chromium; 
 a first population of particulates having a median size less than about 20 nanometers, the particulate phases comprising an oxide phase, the oxide phase comprising titanium and yttrium, wherein a concentration of the first population of the particulate phases at the inner surface is less than a concentration of the first population of the particulate phases at the outer surface, and wherein the concentration of the particulate phases at the inner surface is in a range from about 0.1 volume percent to about 2 volume percent, and the concentration of the particulate phases at the outer surface is in a range from about 0.7 volume percent to about 3 volume percent. 
 
   
     
     
         20 . A method comprising:
 joining a first composition comprising a first oxygen concentration to a second composition having a second oxygen concentration, the second oxygen concentration different from the first oxygen concentration, to form a material comprising a metal matrix and a first population of particulate phases disposed macroscopically non-uniformly within the matrix, the particulate phases comprising an oxide phase.   
     
     
         21 . The method of  claim 20 , further comprising milling an alloy powder comprising iron and chromium in the presence of a first amount of an oxide until the oxide is at least partially dissolved into the alloy powder, thus forming the first composition. 
     
     
         22 . The method of  claim 20 , further comprising milling an alloy powder comprising iron and chromium in the presence of a second amount of an oxide until the oxide is at least partially dissolved into the alloy powder, thus forming the second composition. 
     
     
         23 . The method of  claim 20 , wherein the first composition, the second composition, or both the first composition and the second composition, are powder, and wherein joining further comprises consolidating the powder. 
     
     
         24 . The method of  claim 23 , wherein both the first composition and the second composition are powder. 
     
     
         25 . The method of  claim 24 , further comprising:
 disposing powder comprising the first composition in a first region of a container;   disposing powder comprising the second composition in a second region of the container; and   consolidating the powders and thereby joining the first and second compositions.   
     
     
         26 . The method of  claim 20 , further comprising heating the first composition, the second composition, or the material to form the first population of particulate phases. 
     
     
         27 . The method of  claim 20 , further comprising establishing a second population of particulate phases within the matrix, the second population of particulate phases having a median size in a range from about 25 nm to about 10 microns. 
     
     
         28 . The method of  claim 20 , wherein the first composition and the second composition are solid feedstock, and wherein joining comprises co-extruding, welding, solid-state joining, diffusion bonding, shrink fitting, or a combination thereof. 
     
     
         29 . The method of  claim 23 , wherein the first composition is a solid feedstock and the second composition is a powder, and wherein joining comprises consolidating the powder and bonding the first composition to the second composition. 
     
     
         30 . A method, comprising:
 milling a first powder comprising iron and chromium in the presence of an oxide until the oxide is at least partially dissolved into the alloy powder, thus forming a first composition having a first oxygen concentration;   milling a second powder comprising iron and chromium in the presence of an oxide until the oxide is at least partially dissolved into the alloy powder, thus forming a second composition having a second oxygen concentration that is greater than the first oxygen concentration;   disposing powder comprising the first composition in a first region of a container;   disposing powder comprising the second composition in a second region of the container; and   consolidating the powders and thereby joining the first and second compositions at a temperature to precipitate an oxide phase comprising titanium and yttrium within a matrix comprising iron and chromium;   wherein the first region of the container and the second region of the container respectively correspond to an inner surface and an outer surface of a radially symmetrical body of a turbomachinery component.