Design of environmentally friendly fiberglass compositions: ternary eutectic SiO2–Al2O3–CaO compositions, structures and properties

Incumbent E-glass compositions, which are used for the manufacture of reinforcing fibers for structural composites (e.g., in automotive applications) and for electronic laminates (e.g., in printed circuit boards), contain 6–8% B2O3 and 0.1–1.0% fluorine. B2O3 and fluorine can cause hazardous particulate and toxic vapor emissions during their manufacture. New, environmentally friendly E-glass compositions, which are beginning to replace these compositions in structural applications are fluorine-free and contain either no B2O3, or only small amounts of B2O3. This paper deals with the design of ternary, boron- and fluorine-free fiberglass compositions, which have the lowest possible log 3 fiber forming temperature in the ternary SiO2–Al2O3–CaO system, would be suitable for use in a continuous commercial melt and fiber forming process and would require the lowest possible process energy.