中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 21 No. 9 September 2011 |
（1. School of Materials and Metallurgy, Northeastern University, Shenyang 110819, China;
2. Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,
Wuhan University of Science and Technology, Wuhan 430081, China）
Abstract:Magnesium carbonate whisker as precursor was prepared from the low-grade magnesite tailings by the route of calcination, hydration, carbonation and thermal decomposition, and then MgO whisker was prepared by calcining the precursor. In addition, the effect of MgO whisker addition on sintering and thermal shock resistance of refractory was also investigated. The results show that the thermal decomposition product is MgCO3·3H2O and its morphology is remarkably influenced by the types of additives, and magnesium carbonate whisker with the length of 10−60 μm and length-diameter ratio of 10−20 is successfully prepared when a type of soluble magnesium salt is added. MgO whisker with the length of 10−40 μm is derived from precursor with the heating rate of 1 °C/min. The thermal shock resistance of refractory is significantly improved by the addition of MgO whisker due to its effect on binding and preventing crack expanding, and the proper amount of whisker addition is around 3%.
Key words: MgO whisker; precursor; magnesium carbonate whisker; refractory; thermal shock resistance
