HIGH CORROSION RESISTANT ZINCATE TYPE ZINC-IRON-PHOSPHORUS ALLOY PLATING BATH AND PLATING USING THE SAME PLATING BATH

摘要

PURPOSE: To form a zinc-iron-phosphorus alloy plated film excellent in glossiness, uniform electrodepositing properties and corrosion resistance and to prevent the corrosion of plating equipment by forming the plating bath of an alkaline one in which the value of pH is regulated to the specified value or above and incorporating prescribed amounts of iron, phosphorus and zinc and a phosphorus precipitating assistant therein. ;CONSTITUTION: This zinc-iron-phosphorus alloy plating bath is formed of an alkaline one of pH13, contains, by weight, 0.1 to 30% iron, 0.001 to 1.5% phosphorus, and the balance zinc by the amt. required for electrically precipitating an alloy plating film and furthermore contains a phosphorus precipitating assistant. By allowing the phosphorus precipitating assistant to coexist as the same manner, phosphorus can be incorporated into the plating film, and the plating film excellent in glossiness, uniform electrodepositing properties and corrosion resistance can be obtd. Moreover, this plating bath does not corrode plating equipment. As the phosphorus precipitating assistant, hydroxy carboxylic acid, aminocarboxylic acid, their salts, alcanolamines or the like can be given.;COPYRIGHT: (C)1996,JPO