Direct extrusion of shapes with l12 aluminum alloys

Abstract

A method for producing a high strength aluminum alloy brackets, cases, tubes, ducts, beams, spars and other parts containing L1 2 dispersoids from an aluminum alloy powder containing the L1 2 dispersoids. The powder is consolidated into a billet having a density of about 100 percent. The billet is extruded using an extrusion die shaped to produce the component.

1 . A method for forming a high strength aluminum alloy component containing L1 2  dispersoids, comprising the steps of:
 placing in a container a quantity of an aluminum alloy powder containing an L1 2  dispersoid L1 2  comprising Al 3 X dispersoids wherein X is at least one first element selected from the group comprising:
 about 0.1 to about 4.0 weight percent scandium, about 0.1 to about 20.0 weight percent erbium, about 0.1 to about 15.0 weight percent thulium, about 0.1 to about 25.0 weight percent ytterbium, and about 0.1 to about 25.0 weight percent lutetium; 
 at least one second element selected from the group comprising about 0.1 to about 20.0 weight percent gadolinium, about 0.1 to about 20.0 weight percent yttrium, about 0.05 to about 4.0 weight percent zirconium, about 0.05 to about 10.0 weight percent titanium, about 0.05 to about 10.0 weight percent hafnium, and about 0.05 to about 5.0 weight percent niobium; and 
 the balance substantially aluminum; 
   the alloy powder having a mesh size of less than 450 mesh in a container,   vacuum degassing the powder at a temperature of about 300° F. (149° C.) to about 900° F. (482° C.) for about 0.5 hours to about 8 days;   sealing the degassed powder in the container under vacuum;   heating the sealed container at about 300° F. (149° C.) to about 900° F. (482° C.) for about 15 minutes to eight hours;   vacuum hot pressing the heated container to form a billet;   removing the container from the formed billet; and   extruding the billet into a component using an extrusion die shaped to form the component.   
     
     
         2 . The method of  claim 1 , wherein the aluminum alloy powder contains at least one ceramic selected from the group comprising: about 5 to about 40 volume percent aluminum oxide, about 5 to about 40 volume percent silicon carbide, about 5 to about 40 volume percent aluminum nitride, about 5 to about 40 volume percent titanium diboride, about 5 to about 40 volume percent titanium boride, about 5 to about 40 volume percent boron carbide and about 5 to about 40 volume percent titanium carbide. 
     
     
         3 . The method of  claim 1 , wherein the aluminum alloy powder contains at least one third element selected from the group consisting of silicon, magnesium, manganese, lithium, copper, zinc, and nickel. 
     
     
         4 . The method of  claim 3 , wherein the third element comprises at least one of about 4 to about 25 weight percent silicon, about 1 to about 8 weight percent magnesium, about 0.1 to about 3 weight percent manganese, about 0.5 to about 3 weight percent lithium, about 0.2 to about 6 weight percent copper, about 3 to about 12 weight percent zinc, about 1 to about 12 weight percent nickel. 
     
     
         5 . The method of  claim 1 , wherein the extrusion is carried out at a temperature of from about 300° F. (148.9° C.) to about 900° F. (482.2° C.). 
     
     
         6 . The method of  claim 1 , wherein the extrusion is carried out at rate of about 0.1 inch per minute to about 20 inch per minute. 
     
     
         7 . The method of  claim 1 , the billet temperature ranges from about 300° F. (148.9° C.) to about 900° F. (482.2° C.). 
     
     
         8 . The method of  claim 1 , wherein billet has a soak time ranging from about 0.5 hours to about 8 hours. 
     
     
         9 . The method of  claim 1 , wherein the extrusion is carried out at ratios of about 2:1 to 40:1. 
     
     
         10 . The method of  claim 1 , wherein the extrusion die temperature ranges from about 300° F. (148.9° C.) to about 900° F. (482.2° C.). 
     
     
         11 . The method of  claim 1 , wherein consolidating the powders comprises:
 sieving the powders to achieve a particle size of less than about −325 mesh;   placing the powders in a container with a rectangular cross-section;   vacuum degassing the powder;   sealing the container; and   hot pressing the container to achieve a powder density of about 100 percent.   
     
     
         12 . The method of  claim 1 , wherein the high strength aluminum alloy component is selected from brackets, cases, tubes, ducts, beams, spars and other components for gas turbine engines, rocket engines and other aerospace applications.