Glass Reactivity at High Temperature

Glasses are metastable materials that can evolve during heat treatment. These transformations can be a desired effect to obtain specific properties (self-healing) or to form materials such as glass ceramics or glass foams. It can also be deleterious and alter the optical and physical properties of glass or degrade its chemical durability. In this work, we will show – through different studies performed during the last 10 years the interest of using an Environmental Scanning Electron Microscope (ESEM) equipped with a high temperature furnace to directly observe the formation of crystals in glasses, phase separation, chemical reactivity or glass foaming. We will also endeavor to show the contribution of the use of recently developed devices or methodologies to these studies.