NASA/Marshall Microgravity Science 1998 Science Stories
A challenge in developing advanced materials, such as superalloys, is attaining a precise understanding of the physical properties of the materials when they are molten and taking their final form. However, contact between the material and its container can alter or completely mask those properties. What is needed is a facility that suspends the materials for study while molten. In 1998, NASA/Marshall acquired a sophisticated Electrostatic Levitator.
Right: A 3 mm droplet of molten nickel-zirconium hovers between electrodes inside the ESL during an experiment.
The ESL, directed by Dr. Jan Rogers, uses static electricity to suspend an object inside a vacuum chamber. While that happens, a laser heats the sample until it melts, so scientists can record a wide range of physical properties without contact with the container. An array of sensors measure properties such as viscosity, surface tension, and specific heat. The ESL complements NASA/Marshall's Drop Tube Facility, and expands support for even more sophisticated experiments using space-based facilities.
NASA also continues work on other systems that can process materials without disruption by containers or handling equipment.
1998 Science@NASA stories It floats - New tool levitates molten materials - The Electrostatic Levitator, donated by Loral Space Systems to Marshall Space Flight Center, uses static electricity to suspend small samples in this next generation of ground-based containerless processing. |