Thermo-mechanical Processing Of High-Performance Al-RE Alloys

Abstract

Production of a bulk Al-RE alloy body (product) using cast billets/ingots (cooling rates<100 C/s) or rapidly solidified Al-RE particulates (cooling rates 102-106° C./second) that have beneficial microstructural refinements that are further refined by subsequent consolidation to produce a consolidated bulk alloy product having excellent mechanical properties over a wide temperature range such as up to and above 230° C.

1 .- 10 . (canceled) 
     
     
         11 . A method of making a bulk Al-RE alloy body where Re is Ce, La,
 mishmetal, or any combination thereof, comprising:   rapid solidification processing a molten Al—Re alloy, where Re is Ce, La, mishmetal, or any combination thereof,   forming particulates during or after rapid solidification processing of the molten Al-RE alloy, wherein the particulates are characterized as having a particle microstructure including a strengthening intermetallic phase distributed in an aluminum-rich matrix, wherein the strengthening intermetallic phase is characterized by having a rapid solidification-refined intermetallic phase structure, and consolidating at least one of the particulates and a precursor body comprised of the particulates to form a bulk Al-RE alloy body wherein consolidating is conducted in a manner that fragments at least a portion of the intermetallic phase structure to further refine a consolidated microstructure of the bulk Al-RE alloy body.   
     
     
         12 . The method of  claim 11  wherein the particulates are formed during gas atomization of the molten Al-RE alloy to form gas atomized particles. 
     
     
         13 . The method of  claim 11  wherein the particulates are formed by melt spinning the molten Al-RE alloy to form a ribbon shape followed by pulverizing of the ribbon shape to form flake-shape particles. 
     
     
         14 . The method of  claim 11  wherein rapid solidification processing produces a cooling rate of at least 10 2  to 10 5 ° C. per second and above. 
     
     
         15 . The method of  claim 11  wherein the rapid solidification-refined phase structure includes at least one of a rod, lath, lath spacing, and cell wall thickness. 
     
     
         16 . The method of  claim 15  wherein the rapid solidification-refined phase structure includes a sub-micron average rod dimension, sub-micron average lath dimension, sub-micron average lath spacing dimension, and sub-micron average cell wall thickness. 
     
     
         17 . The method of  claim 11  wherein consolidating further refines the phase structure by forming at least one of individual particle-like lath fragments and rod fragments in the consolidated microstructure. 
     
     
         18 . The method of  claim 17  wherein the at least one of individual particle-like lath fragments and rod fragments has an average dimension in the range of 50 nm to 500 nm. 
     
     
         19 . The method of  claim 11  wherein the consolidating is effected by at least one of extrusion, forging, sinter-forging, rolling, isostatic pressing, spray deposition, and high-velocity oxygen-fuel spray deposition. 
     
     
         20 . The method of  claim 19  wherein consolidating is effected by placing the particulates in a container, which is then extruded to form the consolidated bulk alloy body. 
     
     
         21 . The method of  claim 11  wherein consolidating is effected by compacting the particulates to form a precursor compact, which is then extruded to form the consolidated bulk alloy body. 
     
     
         22 . The method of  claim 11  wherein the strengthening phase comprises Al 11 RE 3  in an amount of about 5 to about 30 weight % of individual particulates. 
     
     
         23 . The method of  claim 11  wherein the strengthening intermetallic phase comprises Al 11 Ce 3 . 
     
     
         24 .- 30 . (canceled)