摘要 |
<p>A plating method comprises the steps of melting the metal and forming a bath of the molten metal, and displacing a strand to be plated longitudinally through the molten-metal bath so the strand leaves the bath at a surface thereof. Thus the molten metal of the bath sticks to the strand and forms a molten metallic layer thereon. A helicoidal, that is at least generally helical or corkscrew-shaped, magnetic field generally centered on the strand is formed and positioned to exert on the metallic layer a magnetic force generally parallel to the strand and on the conductive metallic bath a rotary force centered on the strand. The field is polarized to exert the magnetic force upward to thicken the layer on the strand and is polarized oppositely to exert the magnetic force downward to thin the layer on the strand. The rotary action on the bath serves to move any impurities floating on the bath outward away from the rising strand. Similarly the kneading action of the helicoidal field smoothes the molten-metal layer on the strand so it is of uniform thickness.</p> |