Preparation of Ni-CNT composite coatings on aluminum substrate and its friction and wear behavior
(1. Department of Materials Science and Engineering,
Zhejiang University, Hangzhou 310027, China;
2. Department of Chemistry, Zhejiang University,
Hangzhou 310027, China)
Zhejiang University, Hangzhou 310027, China;
2. Department of Chemistry, Zhejiang University,
Hangzhou 310027, China)
Abstract: Nickel-carbon nanotube(CNT) composite coatings with a Zn-Ni interlayer were prepared by electrodeposition technique on aluminum substrate. The effects of CNT concentration in plating bath on the volume fraction of CNTs in the deposits and the coating growth rate were investigated. The friction and wear behavior of the Ni-CNT composite coatings were examined using a pin-on-disk wear tester under dry sliding conditions at a sliding speed of 0.062 3 m/s and load range from 12 N to 150 N. Because of the reinforcement of CNTs in the composite coatings, at lower applied loads, the wear resistance was improved with increasing volume fraction of CNTs. Since cracking and peeling occur on the worn surface, the wear rates of composite coatings with high volume fraction of CNTs increase rapidly at higher applied loads. The friction coefficient of the composite coatings decreases with the increasing volume fraction of CNTs due to the reinforcement and self-lubrication of CNTs.
Key words: carbon nanotubes (CNTs); composite coating; electrodeposition; friction and wear