Containerless Processing of Glass Forming Melts in Space
Containerless glass forming experiments, which used a single axis acoustic levitator/furnace (SAAL), have been conducted on SPAR rocket flights, VI and VIII, and on Space Shuttle missions, STS-7 and STS-61A. Motion pictures of solid and liquid samples from the most recent experiment (STS-61A) showed that fluid melts can be successfully levitated and positioned with an acoustic field at temperatures up to 1550°C for several minutes. A ternary calcia-gallia-silica glass containerlessly melted in micro-g, provided evidence for a 2 to 3 fold increase in the tendency for glass formation in space. This is preliminary verification that heterogeneous nucleation is reduced in containerless melts. Melt homogenization for this calcia-gallia-silica melt was reasonably fast in space even with the lack of gravity-driven convection. Hot-pressing appears to be a feasible way of preparing precursor samples for use in containerless experiments in micro-g. Comparisons are made with the results of earlier containerless experiments.
D. E. Day and C. S. Ray, "Containerless Processing of Glass Forming Melts in Space," NASA Technical Memorandum, vol. 2, no. 4069, pp. 537 - 556, National Aeronautics and Space Administration, Oct 1988.
Materials Science and Engineering
Keywords and Phrases
Acoustics--Applications; Composite Materials; Glass Furnaces; Space Flight--Weightlessness; Space Shuttles--Zero Gravity Materials Processing; Acoustic Levitation; Calcia Gallia Silica Glass; Containerless Processing; Microgravity; Reduced Gravity Environment; Single Axis Acoustic Levitator/Furnace, Glass
International Standard Serial Number (ISSN)
Article - Journal
© 1988 National Aeronautics and Space Administration, All rights reserved.
01 Oct 1988