By definition, the term “heating” implies disequilibrium because nothing happens when a heating system is at equilibrium. One of our main tools to manage disequilibrium during heating is refractories. These are materials resistant to chemical, thermal and physical damage, specifically chemical reaction, melting, erosion and wear. Refractories serve to contain the charge in a furnace without reacting with the furnace’s contents, to provide some thermal insulation and to absorb physical forces.

Refractories have been used for as long as humanity has built furnaces and ovens – large and small. However, the science of refractories is much younger. For example, recent use of phase diagrams has had a large impact on the reliability of refractories. In addition, an understanding of the detailed chemical and physical interaction of refractories with the furnace contents and of the role of impurities have greatly improved the longevity of refractory linings.