Effect of condensation product on bright zinc electrodeposition from sulphate bath

Abstract

Zinc electroplating is carried out in presence of condensation product formed between <img src='http://www.niscair.res.in/jinfo/smaller.gif' border=0><img src='http://www.niscair.res.in/jinfo/small.gif' border=0>-Alanine and Glutaraldehyde. The bath constituents are optimized through Hull cell experiments. Operating parameters such as <i>p</i>H, temperature, current density are also optimized. Current efficiency and throwing power are measured. Polarization study reveals high shift of potential towards negative direction in the presence of addition agents. Corrosion resistance test indicated good protection of steel by the coating. IR spectrum of the deposit shows the inclusion of the compound. SEM photomicrographs show fine grained deposit in the presence of addition agent. The consumption of brightener in the lab scale is 8 mL for 1000 amp-hour.