Effect of Forming and Aging Atmospheres on E-Glass Strength

E-glass fibers were drawn in various atmospheres. The specific surface area measured by water vapor adsorption was larger than the geometric area. Specific surface increases with the square root of drawing gas pressure. Exposure of glass fibers to ambient atmosphere decreases the strength and increases the area of macropores (r_p> 100 Å). The reciprocal strength of E-glass filaments aged at ambient humidity for various times is proportional to the square root of macro pore area. This relation is independent of the drawing atmosphere, at least for water and tetrafluoromethane.