Crystallization characteristics of iron-rich glass ceramics prepared from nickel slag and blast furnace slag

Zhong-jie Wang,Wen Ni,Ke-qing Li,Xiao-yan Huang,and Li-ping ZhuSchool of Civil and Environmental Engineering,University of Science and Technology Beijing,Beijing 100083,China

摘 要：The crystallization process of iron-rich glass-ceramics prepared from the mixture of nickel slag（NS） and blast furnace slag（BFS） with a small amount of quartz sand was investigated.A modified melting method which was more energy-saving than the traditional methods was used to control the crystallization process.The results show that the iron-rich system has much lower melting temperature,glass transition temperature（Tg）,and glass crystallization temperature（Tc）,which can result in a further energy-saving process.The results also show that the system has a quick but controllable crystallization process with its peak crystallization temperature at 918°C.The crystallization of augite crystals begins from the edge of the sample and invades into the whole sample.The crystallization process can be completed in a few minutes.A distinct boundary between the crystallized part and the non-crystallized part exists during the process.In the non-crystallized part showing a black colour,some sphere-shaped augite crystals already exist in the glass matrix before samples are heated to Tc.In the crystallized part showing a khaki colour,a compact structure is formed by augite crystals.

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