Toward hard and highly crack resistant magnesium aluminosilicate glasses and transparent glass-ceramics |
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Authors: | Xuefei Ke Zhitao Shan Zihuang Li Yunhang Tao Yuanzheng Yue Haizheng Tao |
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Affiliation: | 1. State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan, China;2. Wuhan Britain-China School, Wuhan, China |
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Abstract: | High hardness and high crack resistance are usually mutually exclusive in glass materials. Through the aerodynamic levitation and laser melting technique, we prepared a series of magnesium aluminosilicate glasses with a constant MgO content, and found a striking enhancement of both hardness and crack resistance with increasing Al2O3. The crack resistance of the magnesium aluminosilicate glass is about five times higher than that of the binary alumina-silica glass for the similar [Al]/([Al] + [Si]) molar ratio (around 0.6). For the selected magnesium aluminosilicate glass with R = 0.32, when subjected to isothermal treatment at 1283K, we observed a further drastic enhancement of both hardness and crack resistance by extending the heating time. Based on the structural analyses, we propose an atomic-scale model to explain the mechanism of synergetic enhancement in hardness and crack resistance for the magnesium aluminosilicate glasses and glass-ceramics. |
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Keywords: | aluminosilicates crack growth resistance glass glass-ceramics hardness |
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