Using Lattice Energies to Model the Physical/Chemical Behavior of a Doped Refractory Oxide

Abstract

Burned periclase brick became a commonly used refractory material during the 1940s and early 1950s in the steel-making industry. Unfortunately, periclase brick easily reacts with water or water vapor and results in dimensional instability, i.e., a volume expansion. This may lead to the mechanical failure of any article made from it. Considerable research has been performed in the past 30 years to suppress the hydration susceptibility of magnesia refractory.Boron has been found to be extremely effective in improving the hydration resistance of magnesia. It can be added to magnesite, brucite, light calcined magnesia or it can be deposited on post dead burned magnesia. However, the use of boron decreases the hot loading bearing properties of the magnesia and the dissolution of the boron into certain grades of steel may adversely affect their mechanical properties. Moreover, the addition of boron compounds requires a high-temperature calcination, normally higher than 1600°C, which has been proven uneconomical.Other dopants, incorporated either on the surface or in the bulk, have been reported to have various effects on the hydration susceptibility. The ultimate goal of the work reported here is to determine if there is a correlation between the hydration susceptibility of MgO having various cation substitutions for Mg and the energies of the resulting lattices.