DEVELOPMENT AND OPERATION OF A MICROGRAVITY FURNACE SYSTEM FOR SINTERING EXPERIMENTS

Microgravity experiments have been performed aboard STS-57, STS-60, an d STS-63 with an isothermal high-temperature automated furnace, The eq uipment for controlled liquid phase sintering experiments-SPACEHAB var iant facility was used to conduct powder metallurgy experiments on com pacts at temperatures exceeding 1100 degrees C. An overview of the evo lution of the program from a laboratory mock-up through four sounding rocket flights is presented, including a description of the hardware t hat successfully operated during three Space Shuttle missions, These a ccomplishments were traced directly to the decisions made and numerous lessons learned throughout the applied research program. Development of the hardware required an extremely interdisciplinary approach. A co ntinuous path of upgrades was pursued between Eights, increasing capab ilities while reducing payload mass and volume, This evolutionary expe rience base resulted in significant cost and schedule savings, The des ign features of containment and redundancy with the proven flight perf ormance data minimized expensive component testing and analysis, The h ardware was designed with inherent growth capabilities to maximize saf ety, to promote longterm usage/future flight opportunities, and to sim plify on-orbit operations. The next generation design scheduled to fly aboard STS-79 (August 1996) also is described.