Cyanogen-free plating method of zinc alloy die casting

The invention discloses a cyanogen-free plating method of a zinc alloy die casting. The method is a plating method in which cyanogen-free copper-zinc alloy, copper-stannum alloy or ormolu is subjected to barrel plating or rack plating in a cyanogen-free copper-zinc alloy solution, copper-stannum alloy solution or ormolu solution as grounding layers so as to provide a pre-plating layer with good bonding force for subsequent plating or chemical plating. The method comprises the following steps: (1) carrying out ultrasonic wax removal or tumbling wax removal on a zinc alloy die casting blank; (2) washing; (3) chemically removing oil; (4) washing; (5) activating with 0.5% sulfuric acid; (6) washing; (7) carrying out barrel plating or rack plating on the alloys in the cyanogen-free copper-zinc alloy solution, copper-stannum alloy solution or ormolu solution; (8) washing; and (9) carrying out the subsequent plating or chemical plating. By using the method provided by the invention, cyanogen-free barrel plating or rack plating alloy is carried out on the zinc alloy die casting so that the obtained plating layer is semi-bright and has good bonding force.