(Department of Materials Science and Engineering, Sharif University of Technology,
Tehran, P. O. Box 11155-9466, Iran)
摘 要: 采用放電等離子燒結(jié)制備釔穩(wěn)定氧化鋯(YSZ)增強(qiáng)銅基復(fù)合材料。為作比較，在相同條件下制備了純銅樣品。研究了粒子含量對復(fù)合材料顯微組織、相對密度、電導(dǎo)率和維氏硬度的影響。利用銷-盤裝置研究材料在不同條件下的干滑動摩擦行為。干滑動摩擦測試后，采用場發(fā)射掃描電子顯微鏡對磨損表面進(jìn)行觀察。顯微組織結(jié)果表明增強(qiáng)粒子在銅基體中分布均勻。所有樣品的相對密度都達(dá)到95%以上。當(dāng)YSZ含量從0增加至5%(體積分?jǐn)?shù))時，材料的電導(dǎo)率從99.2%IACS 降至65%IACS。Cu-5%YSZ復(fù)合材料的硬度比純銅硬度大兩倍。在加載載荷為50 N和滑動距離為1000 m條件下，純銅的體積損失和磨損率分別為1.48 mm3和1.5×10-3 mm3/m。而對于5% YSZ增強(qiáng)的復(fù)合材料，其體積損失和磨損率分別降至0.97 mm3和0.9×10-3 mm3/m。此外，材料的摩擦因數(shù)從0.6降至0.4。磨損表面和磨粒觀察結(jié)果表明純銅的磨損機(jī)理為塑形變形和分層，而對于復(fù)合材料，磨損機(jī)理為氧化和犁溝。因此，Cu-YSZ復(fù)合材料可用于要求具有高電導(dǎo)率和熱導(dǎo)率以及耐磨性能的繼電器、電流接觸器，開關(guān)和斷路器。
關(guān)鍵字: 銅基復(fù)合材料；放電離子燒結(jié)；顯微組織；電導(dǎo)率；滑動摩擦
（Department of Materials Science and Engineering, Sharif University of Technology, Tehran, P. O. Box 11155-9466, Iran）
Abstract:In the present study, yttria stabilized zirconia (YSZ) reinforced Cu matrix composite specimens were produced by spark plasma sintering (SPS). For comparison, pure Cu specimen was also produced in the same conditions. The effect of particles content on microstructure, relative density, electrical conductivity, and Vickers hardness was evaluated. The pin-on-disk test was also performed to determine dry sliding wear behavior of specimens under different wear conditions. After sliding wear tests, the worn surfaces were examined by field emission scanning electron microscopy (FE-SEM). Microstructural study showed satisfactory distribution of reinforcement particles in copper matrix. The relative density up to 95% was obtained for all specimens. By increasing YSZ content from 0 to 5% (volume fraction), the electrical conductivity of specimens decreased from 99.2%IACS to 65%IACS, correspondingly. The hardness of Cu-5%YSZ composite specimen was two times greater than that of pure copper. The volume loss and wear rate of pure Cu specimen were 1.48 mm3 and 1.5×10-3 mm3/m under 50 N applied load and 1000 m sliding distance. However, for composite containing 5% YSZ particles, these values dropped to 0.97 mm3 and 0.9×10-3 mm3/m, respectively. Moreover, the friction coefficient of specimens was changed from 0.6 to 0.4. The worn surface and debris observation indicate local plastic deformation and delamination as dominant wear mechanisms for pure copper, while oxidation and ploughing for composite specimen. Accordingly, it can be concluded that the Cu-YSZ composite could be a good candidate for the electrical contact applications in relays, contactors, switches and circuit breakers requiring good electrical and thermal conductivity and capability to resist wearing.
Key words: copper matrix composite; spark plasma sintering; microstructure; electrical conductivity; sliding wear
