ENGINEERING BRASS COATINGS BY SEQUENTIAL PLATING.

Sequential plating plus thermal diffusion provides flexibility and control to precisely engineer electroplated coatings for given applications or to obtain specific coating properties. The effect of diffusion time and temperature on brass chemistry, crystallography, physical and metallurgical properties was investigated. Process control of thermal diffusion by monitoring compositional gradient, zinc oxide thickness, alpha/beta brass ratio, and plated-wire tensile strength discussed. Auger electron spectroscopy was used to study microscopic details of brass coatings, including the chemical species at the surface, variation in chemical composition across the coating thickness, zinc oxide formation, and diffusion mechanisms. Brass plating is an important step in the manufacturing of steel cord for reinforcement of tires. 30 Refs.