Formation of magnesium silicate hydrate in the Mg(OH)2-SiO2 suspensions and its influence on the properties of magnesia castables

作者：Zhang, Yu; Li, Yawei^*; Dai, Yajie^*

来源：Ceramics International, 2018, 44(17): 21365-21373.

DOI：10.1016/j.ceramint.2018.08.190

• Magnesium-silicate-hydrate
• Brucite
• Reactivity
• Magnesia castables
• Explosion resistance
• Mechanical strength

Brucite is an alternative magnesium precursor for magnesia castables. The hydration process of brucite-microsilica suspensions at 50 degrees C was firstly studied to identify the magnesium-silicate-hydrate (M-S-H) formation. The existence of M-S-H was dependent on the characteristics of brucite. The brucite with smaller grain size exhibited higher reactivity and favored the formation of M-S-H. The early strength of magnesia castables with addition of the 1 wt% reactive brucite powder was increased, which was related to the modified microstructure via filling effect of brucite fine particles and the formation of M-S-H. Explosion resistance of castables was improved as well attributed to the enhanced early strength and the M-S-H phase in the presence of reactive brucite. Besides, the facilitated formation of forsterite bonding phase in the brucite containing castables during firing process and the thermal-mechanical strength such as hot modulus of rupture and refractoriness under load were significantly increased.

• 出版日期2018-12-1
• 单位武汉科技大学