Fellow, The American Ceramic Society.
Acetic Acid Role on Magnesia Hydration for Cement-Free Refractory Castables
Article first published online: 14 MAR 2014
© 2014 The American Ceramic Society
Journal of the American Ceramic Society
Volume 97, Issue 4, pages 1233–1241, April 2014
How to Cite
Souza, T. M., Luz, A. P., Braulio, M. A. L., Pagliosa, C., Pandolfelli, V. C. (2014), Acetic Acid Role on Magnesia Hydration for Cement-Free Refractory Castables. Journal of the American Ceramic Society, 97: 1233–1241. doi: 10.1111/jace.12873
- Issue published online: 1 APR 2014
- Article first published online: 14 MAR 2014
- Manuscript Accepted: 29 JAN 2014
- Manuscript Received: 23 OCT 2013
- Magnesita Refratários S.A. (Brazil)
Different approaches to master magnesia hydration in refractory castables have been recently proposed. Among them, the use of hydrating agents can change the Mg(OH)2 crystals morphology and its distribution in the resultant microstructure, minimizing the drawbacks related to the reaction expansion. In this work, the hydrating effect of acetic acid in Al2O3–MgO cement-free castable properties during curing, drying, and firing steps was evaluated by elastic modulus, thermogravimetric, apparent porosity, and SEM analyses. Based on the attained results, adding acetic acid resulted in hydroxide crystals with distinct morphology and flexibility leading to a better accommodation of Mg(OH)2 in the designed microstructure, which inhibited the samples' cracking during curing. In addition, the drying behavior of the evaluated compositions was further optimized by incorporating polypropylene fibers. Thus, this study highlights a novel perspective for fine MgO powders application, indicating that brucite morphology engineering may be a key aspect for the development of advanced Al2O3–MgO cement-free refractory castables.