Magnetic disc, aluminum alloy substrate for magnetic disc, and production method for aluminum alloy substrate

Abstract

Provided are a magnetic disk and a method of fabricating the magnetic disk. The magnetic disk includes an aluminum alloy plate fabricated by a process involving a CC method and a compound removal process, and an electroless Ni—P plating layer disposed on the surface of the plate. The aluminum alloy plate is composed of an aluminum alloy containing 0.4 to 3.0 mass % (hereinafter abbreviated simply as “%”) of Fe, 0.1% to 3.0% of Mn, 0.005% to 1.000% of Cu, 0.005% to 1.000% of Zn, with a balance of Al and unavoidable impurities. In the magnetic disk, the maximum amplitude of waviness in a wavelength range of 0.4 to 5.0 mm is 5 nm or less, and the maximum amplitude of waviness in a wavelength range of 0.08 to 0.45 mm is 1.5 nm or less.

Dependencies are inferred from the claim text.