Electroplating

Claim 1

IN A METHOD OF PLATING ARTICLES WHICH COMPRISES PASSING AN ELECTRIC CURRENT THROUGH THE ARTICLE AND THROUGH THE ELECTROLYTE WHICH, UNDER SUBSTANTIAL AND SATISFACTORY CURRENT DENSITY AND SUSTAINED CONDITIONS OF CURRENT IN A DIRECTION TO MAKE THE ARTICLE CONTINUOUSLY CATHODE, PLATES OUT A ZINC-RICH ALLOY THEREUPON, SAID ELECTROLYTE COMPRISING A BATH HAVING A PH BETWEEN ABOUT 1 AND 3 AND TEMPERATURE BETWEEN ABOUT 70*F. AND 165*F. IN WHICH SALTS OF NICKEL AND ZINC HAVE BEEN DISSOLVED IN SUFFICIENT AMOUNT TO GIVE TO EACH GALLON OF ELECTROLYTE A NICKEL METAL CONTENT OF 8 TO 10 OZS. PER GAL. AND A ZINC METAL CONTENT OF 6 TO 8 OZS. PER GAL., AT LEAST 50% OF THE TOTAL OF THE NICKEL AND ZINC METAL CONCENTRATION IN THE ELECTROLYTE BEING IN THE FORM OF CHLORIDES, THE IMPROVED STEPS COMPRISING PASSING CURRENT THROUGH THE ARTICLE AND THE ELECTROLYTE FOR A TIME PERIOD WITHIN WHICH THE CURRENT FLOW IS BEING PERIODICALLY REVERSED TO MAKE THE ARTICLE ONCE ANODIC AND NEXT CATHODIC IN THAT BATH TO DEPOSIT A NICKEL-RICH ALLOY ON THE ARTICLE, WHEREIN THE CURRENT DENSITY IS OF A VALUE BETWEEN 20 AND 600 AMPS./SQ. FT. IN EACH DIRECTION AND WHEREIN ON ALTERNATE ANODIC AND CATHODIC PULSES THE ANODIC FLOW IS SUSTAINED FOR AT LEAST 2 SECONDS, WITH THE CATHODIC FLOW BEING SUSTAINED FOR A DURATION SUFFICIENT TO APPLY TO THE BATH COULOMBS IN EXCESS OF THE ANODIC FLOW BUT NOT OVER 30 SECONDS AND REPEATING SAID ANODIC AND CATHODIC REVERSAL OF CURRENT FLOW AT LEAST SEVERAL TIMES IN THE DURATION OF SAID TIME PERIOD TO PLATE NICKEL AND ZINC SIMULTANEOUSLY ON THE ARTICLE UNTIL A DESIRED THICKNESS OF THE NICKEL-RICH DEPOSIT HAS BEEN ELECTROPLATED WITH GOOD ADHERENCE TO THE ARTICLE FROM THAT BATH.