| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To effectively prevent not only separation of a plated layer caused by uneven layer thickness but also separation of the plated layer caused by metallic contact corrosion of a piston base. <P>SOLUTION: The base 11 of the piston 8 for the disc brake pressing a brake pad to a disc rotor is composed of aluminum alloy, an iron-plated layer 13 and a chrome-plated layer 14 are stacked on an outer peripheral face of the piston base 11, and potential difference between the aluminum alloy of the piston base 11 and the iron-plated layer 13 as a substrate and that between the iron-plated layer 13 as the substrate and an upper chrome-plated layer 14 are reduced to prevent metallic contact corrosion of the piston base 11, thus the separation of a coating (plated layer) 12 is prevented, brake feeling is stably kept, and a weight is reduced by applying aluminum in the piston base 11. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
