(1. School of Mechanical Sciences, Karunya University, Coimbatore 641114, Tamil Nadu, India;
2. Center for Research in Metallurgy, School of Mechanical Sciences,
Karunya University, Coimbatore 641114, Tamil Nadu, India;
3. Department of Mechanical Engineering Science, University of Johannesburg,
Auckland Park Kingsway Campus, Johannesburg 2006, South Africa)
摘 要: 采用K2TiF6無機(jī)鹽和SiC陶瓷顆粒與鋁熔體原位反應(yīng)制備不同含量TiC顆粒(0, 2.5%, 5%, 質(zhì)量分?jǐn)?shù))增強(qiáng)AA6061鋁合金。為分解SiC釋放碳原子，合金在高溫下進(jìn)行鑄造，并保溫一段時(shí)間。X射線衍射分析表明鋁基復(fù)合材料中只生成TiC顆粒而未見其他金屬間化合物。采用場發(fā)射掃描電子顯微鏡(FESEM)和背散射電子衍射(EBSD)分析AA6061/TiC復(fù)合材料的顯微組織。結(jié)果表明原位生成的TiC顆粒分布均勻，界面清晰，結(jié)合良好，并具有立方、球形和六方等形狀。EBSD圖像表明TiC顆粒對(duì)復(fù)合材料具有明顯的晶粒細(xì)化效果。TiC顆粒可提高鋁基復(fù)合材料的顯微硬度和抗拉強(qiáng)度。
關(guān)鍵字: 鋁基復(fù)合材料；碳化鈦；背散射電子衍射；鑄造；顯微組織；力學(xué)性能
（1. School of Mechanical Sciences, Karunya University, Coimbatore 641114, Tamil Nadu, India;
2. Center for Research in Metallurgy, School of Mechanical Sciences,
Karunya University, Coimbatore 641114, Tamil Nadu, India;
3. Department of Mechanical Engineering Science, University of Johannesburg,
Auckland Park Kingsway Campus, Johannesburg 2006, South Africa）
Abstract:Aluminum alloys AA6061 reinforced with various amounts (0, 2.5% and 5%, mass fraction) of TiC particles were synthesized by the in situ reaction of inorganic salt K2TiF6 and ceramic particle SiC with molten aluminum. The casting was carried out at an elevated temperature and held for a longer duration to decompose SiC to release carbon atoms. X-ray diffraction patterns of the prepared AMCs clearly revealed the formation of TiC particles without the occurrence of any other intermetallic compounds. The microstructure of the prepared AA6061/TiC AMCs was studied using field emission scanning electron microscope (FESEM) and electron backscatter diffraction (EBSD). The in situ formed TiC particles were characterized with homogeneous distribution, clear interface, good bonding and various shapes such as cubic, spherical and hexagonal. EBSD maps showed the grain refinement action of TiC particles on the produced composites. The formation of TiC particles boosted the microhardness and ultimate tensile strength (UTS) of the AMCs.
Key words: aluminum matrix composite; titanium carbide; electron backscatter diffraction; casting; microstructure; mechanical properties
