MANUFACTURING METHOD OF LIQUID BEARING COMPONENTS, MOTOR PROVIDED WITH FLUID BEARING COMPONENTS, AND DISK DRIVE USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method that enables manufacturing a fluid bearing components in which no excessive wear results after long period of operation and offering an excellent productivity. SOLUTION: After forming a metal layer composed of metallic material having a hardness higher than that of copper over the surface of base material of which chief constituent is the copper, dynamic pressure grooves are built on the metal layer by an electrochemical machining. In view of the hardness of the metal layer and the electrochemical machinability, a metal layer had better be a nickel as a main constituent. A metal layer also had better be formed by a plating, because of an uniform metal layer obtained. In order to improve further the abrasion resistance property by increasing the hardness of the metal layer, it is better that an annealing treatment is applied after the metal layer is formed by an electroless nickel plating. The layer thickness of the metal layer is preferable to be in the range of 5-30μm, due to a tradeoff between the depth of dynamic pressure grooves and the uniformity of the layer thickness of the formed metal layer.