Elastic modulus as a tool for magnesia hydration and refractory castables processing evaluation

Considering the difficulties related to the use of MgO in refractory castables, anti-hydration techniques have been proposed, in order to minimize the drawbacks as a result of the magnesia hydration. In parallel, new methodologies should be investigated, aiming better evaluation of the damage caused by the hydration. In this context, a promising technique is the Young's modulus measurement during curing and drying processing steps of refractory castables. In this work, caustic magnesia-containing castables and dead-burned magnesia-containing ones were evaluated by following the elastic modulus profile using the resonance bar method. The evaluation of the initial stages of castables processing (curing and drying) using this technique seemed to be a proper route to detect MgO hydration. The results also highlighted that, compared with usual methods, the elastic modulus measurements results a better sample evolution profile as a function of time and earlier detection of the damage associated with brucite formation.

elastic modulus; magnesia hydration; refractory castables