Patent ID: 6287444
Filing Date: 2001-09-11
Classification: B22F,B23K,C25D

Abstract:
A method for producing a very small metal ball comprising the steps of:using a horizontally turnable plating tank having a cathode located at a turning peripheral portion and an anode centrally located inside the tank, said tank being such that a plating solution charged into the tank is discharged from the turning peripheral portion;cutting a fine metal wire having a diameter D of less than 0.3 mm into metal pieces, each of which has a desired length L which is correlated to the diameter D such that a ratio of the length L to the diameter D is 0.7-1.5;melting and solidifying the thus cut metal pieces to form starting metal pieces;charging the thus formed starting metal pieces into said plating tank; andperiodically repeating rotation and reverse rotation of said plating tank in a desired direction to contact said starting metal pieces with said cathode located at the turning peripheral portion of said plating tank, thereby forming very small metal balls having an outer diameter of less than 1 mm under the conditions of plating said starting metal pieces with a desired metal or alloy, said conditions comprising and ion concentration of 1-70 g/l and a current density of 0.05-10 A/dm.sup.2.