Chemical nickel plating of magnesium and its alloys

Claim 1

THE METHOD OF PLATING WITH NICKEL THE METAL SURFACE OF A WORKPIECE, WHEREIN SAID METAL SURFACE IS FORMED ESSENTIALLY OF MAGNESIUM; SAID METHOD COMPRISING CLEANING AND PICKLING SAID METAL SURFACE, THEN IMMERSING SAID WORKPIECE IN A FIRST AQUEOUS CHEMICAL NICKEL PLATING BATH OF THE NICKEL CATION-HYPOPHOSPHITE ANION TYPE HAVING A PH ON THE ALKALINE SIDE DURING A FIRST TIME INTERVAL SUFFICIENTLY LONG TO PRODUCE AN INITIAL NICKEL COATING HAVING A THICKNESS OF AT LEAST ABOUT 0.1 MIL UPON SAID METAL SURFACE, THEN IMMERSING SAID WORKPIECE IN A SECOND AQUEOUS CHEMICAL NICKEL PLATING BATH OF THE NICKEL CATION-HYPOPOSPHITE ANION TYPE HAVING A PH ON THE ACID SIDE DURING A SECOND TIME INTERVAL SUFFICIENTLY LONG TO PRODUCE A FINAL NICKEL COATING OF DESIRED THICKNESS UPON SAID METAL SURFACE, AND THEN HEAT-TREATING SAID WORKPIECE AT A TEMPERATURE OF ABOUT 400*F. FOR A TIME INTERVAL OF ABOUT ONE HOUR; WHEREIN EACH OF SAID BATHS COMPRISES NICKEL IONS, HYPOPHOSPHITE IONS IN THE RANGE OF 0.15 TO 1.20 MOLES/LITER, AND A RATIO BETWEEN NICKEL IONS AND HYPOPHOSPHITE IONS IN THE RANGE OF 0.25 TO 1.60.