Surface activation pretreatment for cobalt alloys electroplating

• Published in: Jurnal Tribologi
• Main Author: Hyie K.M.; Budin S.; Roseley N.R.N.; Nawawi N.A.; Yusoff H.; Suhaimi S.
• Format: Article
• Language: English
• Published: Malaysian Tribology Society (Mytribos) 2022
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85128332151&partnerID=40&md5=07f7107d8ac615062c2666d4dd754795

A protective coating is a common solution applied in industry to resist the steel from rusting. The coating must be homogeneous and smooth to ensure strong adhesion with the steel. A crucial step for this to be achieved is the activation pretreatment. The aim of this study is to investigate the effect of the activation step on the cobalt alloy coating performance. This was done by acid dipping low carbon steel into nitric acid solution at different concentrations (3 vol%, 5.5 vol%, and 10 vol%) and dipping time (35 s and 45 s). The steel was then deposited with a cobalt alloy coating using the electroplating process. The final product was characterized using XRD, SEM, EDX, surface roughness and Vickers hardness tester. It was observed that the coated product achieved the lowest surface roughness of 0.528 mm and the highest Vickers hardness of 346.7 HV when the concentration of activator was at 10 vol% and dipping duration of 45 s. It is concluded that a well-designed activation pretreatment process is crucial before the electroplating process is conducted to produce notable coating protection. © 2022, Malaysian Tribology Society (Mytribos). All rights reserved.