Cr/nanodiamond composite plating with cobalt cation additive

• Published in: Transactions of Nonferrous Metals Society of China 2009-08, Vol.19 (4), p.975-978
• Main Authors: NGUYEN, Viet-Hue, HOANG, Thi-Nam, NGUYEN, Ngoc-Phong, KWON, Sik-Chol, KIM, Man, LEE, Joo-Yul
• Format: Article
• Language: English
• Subjects: composite plating; corrosion; microhardness; nano-powder; wear rate; 复合镀层; 形态观察; 扫描电子显微镜; 添加剂; 纳米金刚石粉; 金刚石颗粒; 钴离子
• ISSN: 1003-6326
• DOI: 10.1016/S1003-6326(08)60389-1

The effect of cationic additive on Cr/nanodiamond plating was studied. Chromium plating was performed in Sargent bath. Morphology of deposit was observed by scanning electron microscope（SEM）; microhardness by hardness tester; wear rate by tribometer; amount of diamond in deposit by combustion method and passivity by potentiodynamic scan. Experimental results show that in the presence of cobalt cation, the amount of nanodiamond particle in the deposit is increased. With increasing diamond particle amount, the metallurgical, mechanical and electrochemical properties of Cr/nanodiamond deposit are improved. However, this improvement seems to be constrained. In the presence of 10 g/L of nanodiamond powder and 2.5 g/L of cobalt cation in the bath, the amount of diamond, particle in deposit is increased by 4 times; and wear rate of Cr-Co/nanodiamond deposit is decreased by 2-3 times as compared with pure Cr/deposit. The passive current of Cr-Co/nanodiamond composite deposit is decreased from 18 to 8 μA. The morphology of Cr/nanodiamond is smooth remarkably in the presence of cobalt cation.