セルロース・ナノ・ファイバーを用いたC/Cコンポジットの摩擦摩耗特性に及ぼす温度・通電環境の影響

抄録

Bacterial cellulose (BC) is a natural fiber synthesized by bacterium. The Authors have already developed materials, that is, C/C composites, having high wear resistance with BC and phenol resin. In this paper, in order to apply the mBC-C/C composite to the carbon brush of DC motors, the basic experiments were conducted to clarify tribology properties of the developed materials under current conduction and thermal condition. The composite specimens were prepared by carbonizing the BC/Phenol FRP plates at the temperatures of 700°C to 1000°C. The dry sliding wear test was carried out against the Oxygen Free Copper (OFC) and SUS304 counter face materials by using a pin on drum type tribology apparatus. As the results of the sliding tests with OFC rotor as a friction mating material, the coefficient of dynamic friction took the high value over 1.0. In addition, the electrical resistivity of composite was measured at the room temperature, and its mean value was 2.72×10^-4 Ωm. Additionally, the fabrication methods of the BP-C/C composites with BC and Bamboo charcoal Particle (BP) as Si additive were also developed. The effect of BP mass content on the wear and friction properties was investigated experimentally. From the wear test results, the wear and friction properties of the BP-C/C composites were dependent on BP mass content and carbonizing temperature. The composites with 5wt% BP carbonized at 900°C indicated the lowest friction coefficient of 0.15 among the composites. On the other hand, the composites with 5wt% BP carbonized at 1000°C exhibited the lowest wear rate of 2.25×10^-10 [mm²/N]. The experimental results indicated that BP can be applied as fillers which can provide lower wear and friction properties to the composites.