Interfacial reaction between SiO2-Al2O3-ZnO-CaO based glass coating and K38G superalloy results in gaseous products of Zn and/or Na, and bubbling surface of the glassy coating. With incorporation of alumina particles, however, intact glass/alumina composite coating, which can restrict progressing of the excessive interfacial reaction, is formed on the alloy substrate. Enhanced high-temperature strength and viscosity of glass by alumina particles incorporation ensure the composite glassy coating with high stiffness and compactness which inhibits escape of Zn and/or Na gases from the interface, accounting for its suppressing effect on interfacial reaction. (C) 2013 Elsevier B.V. All rights reserved.