Title: Electroplating on zinc based alloy
Application Number: 85100201 Application Date: 1985.04.01
Publication Number: 1003319 Publication Date: 1986.09.17
Approval Pub. Date: Granted Pub. Date: 1989.09.13
International Classifi-cation: C25D5/34
Applicant(s) Name: Changling Machine Factory Address:
Inventor(s) Name:
Attorney & Agent: GU LUXIANG
Abstract:
     This invention concerns a new method for electroplating coppemr, silver, and chrome on the zinc based alloy, it can also be applied to electroplate weldable gold, silver and tin film on the zinc based alloy. The process comprises two steps, pretreatment prior to electroplating and electroplating. The composition of pretreating solution is: HEDP, sodium hydroxide, potassium citrate, and some disodium-EDTA may be added also. Zincate treatment and copper cyanide plating are then applied. Finally, the copper, nickel, chrome films or the gold, silver and tin films are electroplated. On electroplating copper, nickel and chrome, an impulse of the high voltage and great current is required for 0.5-1 minute at beginning, so the plated film will not blister, neither peel off, nor be marked with black stripes or black spots. Over 98% of the product will meet the required specification.
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