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Optical and Mechanical Properties of Glass Blown In VacuoTheoretically, the strength of glass processed in vacuum should be higher due to outgassing of contaminants normally present in the glass, such as bulk water in the form of OH bonds that tends to weaken the glass structure. In this research, small discs of a few types of glass have been subjected to various temperatures for extended periods of time in vacuum. Their strength was then tested using a standard flexure technique, facilitated by a custom-designed test fixture, and the results were compared to glass tested in air using the same fixture. The purpose of the glass blowing investigation was to prove the basic feasibility of a high-level concept for in-space manufacture of optical elements. The central requirement was that the glass bubble had to be blown into a support structure such that the bubble could be handled by manipulation of the structure. The blown bubble attached itself to a mullite ring geometrically and mechanically, as a demonstration in the initial experiments described here, by expanding through and around it. The vacuum system used was custom made, as were most of the components of the system, such as the heating element, the glass and ring support structure, and the gas inlet system that provided the pressure needed to blow the glass.
Document ID
20060048182
Document Type
Preprint (Draft being sent to journal)
Authors
Manning, andrew (Alabama Univ. Huntsville, AL, United States)
Tucker, Dennis (NASA Marshall Space Flight Center Huntsville, AL, United States)
Mooney, Theodore (Alabama Univ. Huntsville, AL, United States)
Herren, Kenneth (NASA Marshall Space Flight Center Huntsville, AL, United States)
Gregory, Don A. (Alabama Univ. Huntsville, AL, United States)
Date Acquired
August 23, 2013
Publication Date
January 1, 2006
Subject Category
Mechanical Engineering
Distribution Limits
Public
Copyright
Other