PURPOSE: To detect minute cracks on the surface of metal parts by permitting a micell electrolytic method to precipitate clear pigment at the cracks.
CONSTITUTION: In this minute cracks detecting method, an insulating coat 5 is formed in advance on a metal surface for detecting a minute crack 8 developing on the metal surface of a metal parts 6, oxidization-reduction part and micell series performance are also provided. An aqueous solution of surfuctant, e.g. a ferrocene, with which oxidization or reduction at an oxidization-reduction part collapses micell, is dispersed with pigment or dye to produce an electrolyte, i.e. in a ferrocene 2 water solution is a detection liquid 7. In addition, with a metal as an anode, a voltage is applied between the anode and a counter electrode, thus precipitating pigment only at a cracking part.
YAMAGUCHI TAKUO
OSAWA YASUHIKO
