To provide an electrolytic surface-roughening technology for forming extremely fine pits in a surface of a metal material in a high density, which is performed especially at normal temperature, and which provides a dense roughened surface in a short period of time.
Fine electrolytic pits are formed in a surface of an anode metal by using a following liquid as an electrolytic solution and a metal, and holding the electric potential difference between an anode (the metal) and a cathode within "a steady region B" of an anode polarization curve. The electrolytic solution is a solution containing an electrolyte and 0.2-10 mass% water in an organic solvent. The metal is an iron-based alloy or a nickel-based alloy containing 9-35 mass% of Cr and is characterized in that an active dissolution peak A, "the steady region B", and a current-rising region C are observed from the low electric potential side in the anode polarization curve (wherein, an axis of abscissa is electric potential difference, an axis of ordinate is current density), obtained by using the electrolytic solution.
COPYRIGHT: (C)2010,JPO&INPIT
FUJIMOTO SHINJI
IWAMIZU YOSHIHARU
SAITO MINORU
Kenji Wada