Effect of Various Operating Parameters on Trivalent Chromium Electroplating
Md. Ehasanul Haque *
Department of Materials Science and Engineering, University of Rajshahi, Bangladesh and School of Materials Science, Japan Advanced Institute of Science and Technology (JAIST), Japan.
Md. Asadul Hoque
Department of Materials Science and Engineering, University of Rajshahi, Bangladesh.
Md. Mayeedul Islam
Department of Chemistry, Rajshahi University of Engineering and Technology (RUET), Bangladesh.
Md. Saidul Islam
Department of Materials Science and Engineering, University of Rajshahi, Bangladesh.
Chand Mohammad Mustafa
Department of Applied Chemistry and Chemical Technology, University of Rajshahi, Bangladesh.
*Author to whom correspondence should be addressed.
Abstract
The investigation was aimed to electrodeposit chromium on mild steel surface from non-toxic trivalent chromium bath instead of toxic hexavalent chromium employed for this purpose. We observed the effect of pH, temperature, current density (C.E.) and also time on to the current efficiency. On the other hand we also observed the effect of the concentration of CrCl3 on the plating thickness and optical reflectivity. The optimum pH value and bath temperature are 3 and 40°C respectively to obtain highest current efficiency. On the other hand, 90 min deposition time was the best for high current efficiency. We also achieved good current efficiency at 20 A/dcm2 current density. But the plating thickness was increased with increasing the CrCl3 concentration in the electrolyte. In case of optical reflectivity, the result is totally opposite. Our findings will contribute to develop the products of plating industries.
Keywords: Trivalent chromium, current efficiency, plating thickness, optical reflectivity