ZHANG Yangfan,DUAN hongjuan, ZHANG Haijun, TIAN liang
(The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology,
Wuhan 430081, Hubei, China)
Abstract: In order to control the hydration of magnesium oxide, effects of different additives on the hydration of magnesium oxide were discussed. The hydration of magnesium oxide was characterized by the weight loss of the samples after heat treatment. The phases and the morphology of the products were investigated by powder X-ray diffraction (XRD) and scanning electron microscope (SEM). The results showed that: (1) ammonium chloride (NH4Cl) and magnesium acetate (Mg(CH3COO)2·4H2O) accelerated the hydration of magnesium oxide, which could lead to poor flowability and short setting time; (2) tartaric acid (C4H6O6) inhibited the hydration of magnesium oxide, which could lead to better flowability and long setting time.
Key words: refractory castable; magnesia; hydration