The compressive stress-strain behavior of an Al-Al_3Ti ally produced by mechanical alloying under liquid nitrogen has been investigated over a rnage of elevated temperatures and strain rates. The alloy consists of sub-micrometer grains of Al and Al_3Ti that contain nanosized dispersoids. The microstructure is extremetly stable, even at 0.75 T_m. The alloy exhibits good high temperature strength and ductility, but little work hardening or softening. Pronounced threshold behavior, strongly temperature dependent, is attributed to the stress required to detach dislocations from the dispersoids. A yield point phenomenon, observed at high temperatures and fast strain rates, is beliveved to be a consequence of the low initial dislocation density in the Al grains.
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