摘要 |
1,230,491. Mechanical plating. MINNESOTA MINING & MFG. CO. July 16, 1968 [July 17, 1967], No.33887/68, Heading C7F. Small metal parts are coated with metal by immersing them in an aqueous cleaning solution containing strong acid and agitating until said parts are essentially clean, adding finely divided mechanical coating metal to the aqueous cleaning solution containing the cleaned parts and agitating said solution until the desired thickness of mechanical coating metal is deposited on said parts in the soiled cleaning solution. Chemical dispersing means for the coating metal and corrosion inhibitors and surfactants may be added to the solution. Adhesion of the coating metal to the substrate may be enhanced by a first flash-coating of metal applied in the same solution by displacement or galvano mechanical techniques after the cleaning step. Ferrous metal may be flash-coated with Sn and then coated with zinc, and many other examples are given relating to Fe with flash-coatings of Cd, Pb, Sn, or Cu and final coatings of Zn, Cd, Sn or Pb. |