Interfacial reaction between SiO2-Al2O3-ZnO-CaO based glass coatings and K38G superalloy substrates

► Interfacial reaction between glass coating and superalloy substrate is considered. ► Zinc gas products resulted in bubbling of glass coating. ► Loose TiO2 interlayer leads to spalling off of glass coating. ► Pre-crystallization of glass coating suppressed interfacial reaction.