Method for manufacturing an oxide thin film of titanium or a titanium alloy with fine pores sealed

摘要

PROBLEM TO BE SOLVED: To provide a method for producing an oxide thin film of titanium or a titanium alloy in which micropores are sealed. An electrolytic treatment apparatus 1 has a treatment tank 2 and a cathode member 4 and an anode member 5 installed in the treatment tank 2, and the cathode member 4 and the anode member 5 are each negative of a DC power supply 3. It is connected to the pole and the positive pole. In this electrolytic treatment apparatus 1, the anode member 5 is a member to be treated, and a member using a thin film made of titanium or a titanium alloy is used. In this treatment tank 2, an electrolytic sulfuric acid solution S in which a hydrogen fluoride compound is dissolved in an amount of 0.5% by weight or less and having an oxidizing agent concentration of 5 g / L or more is housed and electrolyzed at a current density of 1 to 20 A / dm2 (pore opening step). ). After that, electrolytic treatment is performed at a current density of 0.1 A / dm2 or less (pore sealing step). [Selection diagram] Fig. 1