To provide a fine crystallite high-performance metal alloy member in which various characteristics are enhanced by eliminating its defects without losing its excellent characteristics, to provide a manufacturing method therefor, and to provide business development using the same.

A metal alloy crystallite containing a high-purity alloy having a crystal lattice that is a face-centered cubic lattice, a body-centered cubic lattice, or a close-packed hexagonal lattice is refined into a nanometer size (10^-9 m to 10^-6 m) and a micrometer size (10^-6 m to 10^-3 m), and the shape of the metal alloy crystallite is adjusted.