次世代自動車端子向けの高導電性・耐摩耗性Ag–Graphene複合めっき膜の創製

抄録

The purpose of this study is to clarify the effects of electroplating conditions and the graphene size on the properties of Ag–Graphene composite films that electrodeposited on Cu alloy as terminals and/or connectors for automobiles. It was found from the measurement results of electrical contact resistance that the conductivity of the Ag–Graphene composite films was highly dependent on the current density during electroplating. The electrical contact resistance of the Ag–Graphene composite films decreased gradually with plating current density, giving a lowest value of 0.25 mΩ at 0.5 N, or in other words, improving the conductivity for 59％ than the pure Ag film. This can be attributed to the fact that the composited graphene sheets had fewer defects when the current density was increased. Moreover, the conductivity or the electrical contact resistance stability can be maintained even after heating at 200°C for 1000 h due to the excellent thermal stability of graphene. Furthermore, it was also found from wear tests that the graphene size included in the composite films plays a significant role in the abrasion resistance of the Ag–Graphene composite plating films. In particular, the Ag–Graphene (3–5 μm) composite film exhibited the best wear resistance, with a 69％ reduction in the friction coefficient and a 95％ reduction in the worn amount after sliding friction for 100 cycles under 3 N.