| AVS 61st International Symposium & Exhibition | |
| Thin Film | Thursday Sessions |
| Session TF-ThP |
| Session: | Thin Films Poster Session |
| Presenter: | Shoko Yamada, Aichi Institute of Technology, Japan |
| Authors: | S. Yamada, Aichi Institute of Technology, Japan H. Ito, Aichi Institute of Technology A. Matsumuro, Aichi Institute of Technology, Japan |
| Correspondent: | Click to Email |
Surface modification of forming many kinds of films must be one of the most important technologies. For especially many kinds of plating methods are already established and easy processing to the product of complicated forms. Furthermore, the composite plating which contains many kinds of small particles in the film are also fabricated and it contributes to the further improvement in the characteristic.
In this study, we focused on development of Ni composite plated films reinforced by dispersed multi-walled CNT with 50 nm in the diameter and several μm in the length using the ultrasonic vibration. An ordinary electroplating method was applied at room temperature. CNT/Ni composite plated film was examined under the conventional plating conditions of pH 4.5-4.7 using a Ni plate as an anode and a Cu plate as a cathode. The mixing weight concentrations of CNT were changed in the range of 0-0.1 wt.%CNT to the weight of the plating bath. It is necessary to prevent from aggregation of CNT in composite plated films because the aggregation parts of CNT must surely cause a loss of strength of the materials. In order to distribute CNT molecules in the plating solution, the ultrasonic vibrations was applied for 1 h before the plating process. The operation conditions was set constant as follows; the bias voltage of 3.7 V, the current density of 3.0 A/dm2 and the plating time of 10 minutes. Thickness of plated film obtained was about 40 μm. Fabrication of CNT/Ni composite films of all mixing weight ratio plated on a Cu plate was confirmed with flat surfaces. But the remarkable condensation parts were observed at the surface at the weight ratio of 0.1 wt.%CNT. The X-ray diffraction experiments clearly indicated no formation of any compound between Ni metal and CNT, because only Ni crystalline diffraction patterns for all CNT concentrations were identified. Vickers hardness tests showed that the hardness increased with the increase of concentration up to 310 Hv of 0.07 wt.%CNT, and decreased after that. This maximum hardness was about twice of the value of the pure Ni plated film. The decrease of hardness over the concentration of 0.07 wt.%CNT should be due to existence of softer aggregate part CNT in the composite films. The friction and abrasion characteristics were also estimated using by a pin-on-disk tester under the load of 0.5 N with a stainless steel pin. It was clarified that the friction coefficient of the composite film with concentration of 0.07 wt.%CNT decreased to 0.5 in comparison with pure Ni coating of 0.8 and showed an unobservable abrasion mark.
From the above results, industrial validity of this study was surely able to be found out.