One. Scientific Foundations of Hollow Glass Microspheres one.1 Composition and Microstructure 1.one.1 Chemical Composition: Borosilicate Dominance Hollow glass microspheres (HGMs) are primarily made up of borosilicate glass, a cloth renowned for its lower thermal enlargement coefficient and chemical inertness. The chemical makeup ordinarily incorporates silica (SiO₂, 50-90%), alumina ... https://talkitter.com/post/458077_metallic-boride-powders-are-very-unique-but-functional-new-ceramic-materials-the.html