ALUMINUM ALLOY BLANK FOR MAGNETIC DISK HAVING EXCELLENT MACHINABILITY AND METHOD FOR PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an aluminum alloy blank for a magnetic disk which can prolong the service life of a bite compared with the conventional one, and a method for producing the same. SOLUTION: The annealed aluminum alloy blank for a magnetic disk having excellent machinability is composed of a substrate of an Al-Mg alloy comprising 3.5 to 10 mass% Mg and an oxide film formed on the surface of the substrate. The average film thickness of the oxide film is≤15 nm, and the average composition of the oxide film satisfies 0.05≤Mg/(Al+O+Mg)≤0.25 by the atomic numbers of Al, O and Mg. The production method for the same is provided. COPYRIGHT: (C)2011,JPO&INPIT