| 摘要 |
The invention provides a method for producing a fiberizable borosilicate glass in which the constituents of the glass composition are classified into two or more melting groups. A molten base glass portion which is free of at least a major portion of the boric oxide yielding ingredients is prepared, and the remainder of the glass composition including the boric oxide yielding ingredients is introduced and homogenized with the molten base glass external to the base glass melting area, thereby to form a molten glass composition of desired characteristics. The invention is particularly adaptable to the formation of borosilicate glass fibers; the ingredients for the glass fiber are separated into those for forming a host glass and those for forming a B2O3-containing additive glass. The ingredients for the host glass are melted in a continuous flow main-melter and flowed from the main-melter to a location where the fibers are to be formed. The additive glass is separately melted, and combined (with forceful mechanical mixing) with a larger portion of the molten host glass prior to the fiber-forming location, to form a fiberizable borosilicate glass. Since at least a major proportion B2O3 content of the fiber is supplied by the additive glass, the main-melter exhibits longer life and the volatilization losses of B2O3 are substantially less than when the ingredients of the additive and host glass are melted together in the mainmelter. |
