Research of Microstructure and Wear-Resistance on the CaO-Al_2O_3-SiO_2 Glass-ceramics

Abstract: In recent years, with the development of the glass-ceramics industry of CaO-Al_2O_3-SiO_2 system, and the rise of the decorations, a large number of buildings have used the building decorated glass-ceramics already. But after using for a certain time, the scratching phenomenon that the building decorated glass-ceramics surface will appear, make it lose its already existing ornament effect, and limit the range of application.The subject takes the CaO-Al_2O_3-SiO_2 glass-ceramics of which main crystallization phase is P-wollastonite as the research object, prepares the glass-ceramics by sintering .The kinds, sizes and contents of the crystallization are controlled by adjusting the content of the basic glass components, such as CaO and Al_2O_3. The relationship between the content of components and the wear-resistance performance of the glass-ceramics is studied, and analyzes its impact on its microstructure and mechanics performance, such as hardness, etc. In addition, ZrO_2 is imported directly to increase the toughness of the glass-ceramics, and the influence of ZrO_2 on microstructure and wear-resisting performance is researched. Also the effect of ZrO_2 on the sintering and crystallization of the glass-ceramics is investigated at the same time.Abrasion wear is taken as the main wear mode in the experiments. The zircon of 60 and 130 meshes, and the SiC of 130 meshes are used as the abrasives, in order to test the wear-resisting performance of the glass-ceramics on the wear-testing machine. The wear mechanism is studied after the wear test by observing the surface microstructure.The experimental results shows that the increase of CaO promotes the crystallization of glass-ceramics, thus improves the wear-resisting performance of the material; The introduction of Al_2O_3 reduces the crystallization inclination of the glass, but can make the vitreous body more compacted , and also improves the mechanics performance of the glass phase, synthesizes two kinds of effect, the wear-resistance of the glass-ceramics has got the improvement of a certain degree; The intake of ZrO_2 improves the viscidity of the glass, and has a baffling effect on sintering shrinkage of glass particle, and negative effect on the sintering of the glass-ceramics. However, the intake of ZrO_2 promotes the crystallization of glass-ceramics, and can also increase the toughness of the materials, so the wear-resistance is finally improved.In the testing experiments, as to zircon abrasive , the bigger the particle is , the heavier the wearing is ; To the different abrasives, zircon and SiC, the hardness of zircon is higher than SiC, its wearing amount is far greater than SiC. In the low wearing area of the loose abrasive of tiny particle, wear mechanism is mainly the micro-cuts wearing mechanism, and the surface has obvious furrow and indentation. In the high wearing area of the big particle, wear behavior includes many kinds of mechanism, and the superficial microstructure is also very complicated…
Key words: glass-ceramics ; wear-resistance ; toughness ; wear-mechanism

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