As glassmakers we are all very aware of gravity and its affect on glass making. NASA researchers have conducted experiments with forming and shaping glass in micro-gravity. This allows a very high-quality glass to be formed. Below is an excerpt from an article called Glass From Space, from NASA Science News. The article talks about experiments of shaping glass in micro-gravity using an acoustic levitator. My question is how do I get my hands on this?
“NASA supported researchers have discovered that Glass formed in space has remarkable properties.
Going into those first experiments, he says, he expected to end up with a purer glass. That’s because on Earth, the melts–the molten liquid from which glass is formed–must be held in some kind of container. That’s a problem. “At high temperatures,” says Day, “these glass melts are very corrosive toward any known container.” As the melt attacks and dissolves the crucible, the melt–and thus the glass–becomes contaminated.
In microgravity, though, you don’t need a container. In Day’s initial experiments, the melt–a molten droplet about 1/4 inch in diameter–was held in place inside a hot furnace simply by the pressure of sound waves emitted by an acoustic levitator.
With that acoustic levitator, explains Day, “we could melt and cool and melt and cool a molten droplet without letting it touch anything.” As Day had hoped, containerless processing produced a better glass. To his surprise, though, the glass was of even higher quality than theory had predicted.
In Earth-orbit, it turns out, these molten liquids don’t crystallize as easily as they do on Earth. It’s easier for glass to form. So not only can you make glass that’s less contaminated, you can also form it from a wider variety of melts.
But why is that important? What’s wrong with glass made of silica?”
To read the full article click here.
– Jessica Jane Julius