(中南大學(xué) 粉末冶金國(guó)家重點(diǎn)實(shí)驗(yàn)室,長(zhǎng)沙 410083)
摘 要: 分別采用不同粒度鱗片石墨(鱗片石墨Ⅰ、Ⅱ、Ⅲ)和瀝青石墨通過(guò)粉末冶金法對(duì)銅石墨電刷材料進(jìn)行制備,采用XRD和SEM對(duì)其試驗(yàn)前后的物相和組織形貌進(jìn)行分析,并運(yùn)用XPS分析對(duì)偶件的表面成分。結(jié)果表明:隨著石墨粒度的下降,銅石墨電刷材料的燒結(jié)密度、硬度和抵抗磨粒磨損的能力均有所下降,抵抗電弧燒蝕的能力則顯著提高。瀝青粘結(jié)劑能夠促進(jìn)銅和石墨的均勻分布,從而改善材料的物理力學(xué)性能和摩擦磨損性能。此外,產(chǎn)生于摩擦界面的CuO降低材料的導(dǎo)熱導(dǎo)電能力并催化石墨氧化,從而加劇磨損。
關(guān)鍵字: 石墨粒度;瀝青粘結(jié)劑;摩擦;磨損;氧化
(State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China)
Abstract:Copper-graphite brushes were fabricated through powder metallurgy method by flake graphite with different sizes (graphiteⅠ, Ⅱ, Ⅲ) and pitch binder. The original phase components and structure morphologies were compared with the worn sample by using X-ray diffraction and scanning electron microscopy, respectively. The surface components of counterparts were studied by X-ray photoelectron spectroscopy. The results indicate that physical properties and the ability to resist the abrasive wear will be worse with the graphite granularity decreasing. However, the arc ablation will be enhanced. Uniform distribution of copper and graphite can be achieved by adding pitch binder, which improves the physical and mechanical properties and friction and wear properties. Furthermore, copper oxide generated from friction interface will reduce the thermal and electrical conductivity and catalyze graphite oxidation, which exacerbates the wear performance.
Key words: graphite granularity; pitch binder; friction; wear; oxidation


