Dispersion strengthening of aluminum alloys by reaction of unstable oxide dispersions
Abstract
Abstract A method for preparing dispersion-strengthened metal consisting predominantly of aluminum metal as the metal matrix is provided comprising ball milling said metal as a powder with an unstable oxygen compound whose free energy of formation per gram-atom of oxygen at 500* C. is less than that of the oxide of said metal matrix and which undergoes reaction with said metal matrix at said temperature to form a stable oxide dispersant in a hermetically sealed mill under an inert atmosphere in the presence of a grinding liquid. The resulting flake metal having homogeneous dispersions of the included oxide is then reacted in a nonoxidizing environment at a temperature of about 500* C., pressed, and hot extruded to form the dispersion strengthened product. Extruded bar material containing only 4 weight percent oxide dispersant exhibited super elevated temperature strength when compared to conventional sintered aluminum product containing up to 15 weight percent oxide dispersant. Another alloy showed improved low strain rate fracture ductility with good strength at high temperature when compared to sintered aluminum products.
Inventors
- 👤 Joseph P Hammond
Bibliographic Details
Claims Analysis
Total Claims: 1References Cited (Backward Citations)
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