The second voyage of the SPACEHAB Space Research Laboratory carried 11 industry-driven experiments sponsored by more than 20 U.S. companies working through five of NASA's Centers for the Commercial Development of Space. The laboratory also carried one NASA accelerometer, one NASA technology demonstration/verification experiment, and one JPL materials exposure experiment.

Just as with SPACEHAB-1 in June-July 1993, the SPACEHAB-2 experiments represented a wide range of space experimentation. The two industry-driven materials processing experiments used furnaces, one studying sintering of powder and liquid metals and the other growing crystals in vapor. The eight industry-driven biotechnology experiments ranges from improving drugs to feeding plants, from splitting cells to studying immune disorders. There was also one industry accelerometer onboard to characterize the low-gravity environment of the laboratory.

Commercial Materials Processing Experiments

1. Equipment for Controlled Liquid Phase Sintering Experiments

The Consortium for Materials Development in Space (CMDS) based at the University of Alabama in Huntsville (UAH) developed the Equipment for Controlled Liquid Phase Sintering Experiments (ECLIPSE). Wyle Laboratories supported the development of ECLIPSE which flew successfully on STS-57 SPACEHAB-01. This furnace was developed in a very rapid and cost-effective manner. ECLIPSE is now available as space-qualified hardware and is a key part of this nation's commercial space infrastructure.

On STS-60 SPACEHAB-2 the ECLIPSE experiment investigated the Liquid Phase Sintering (LPS) of metallic systems. Sintering is a well-characterized process by which metallic powders are consolidated into a metal at temperatures only 50% of that required to melt all of the constituent phases. In LPS, a liquid coexists with the solid, which can produce sedimentation, thus producing materials that lack homogeneity and dimensional stability. To control sedimentation effects, manufacturers limit the volume of the liquid. The ECLIPSE experiment examines metallic composites at or above the liquid volume limit to more fully understand the processes taking place and to produce materials that are dimensionally stable and homogeneous in the absence of gravity.

The ECLIPSE project is focused on composites of hard metals in a tough metal matrix. This composite will have the excellent wearing properties of the hard material and the strength of the tough material. Applications of such a composite include stronger, lighter, more durable metals for bearings, cutting tools, electrical brushes, contact points and irregularly-shaped mechanical parts for high stress environments. Kennametal, Inc., is an industry partner of the UAH CMDS participating in the ECLIPSE experiment, and has immediate applications for material improvements in the ceramic composites tested. Kennametal, one of the nation's largest cutting tool manufacturers, is developing stronger, more durable tool bits and cutting edges. Other industry partners on the ECLIPSE project are Wyle Laboratories, Automatic Switch Company, Parker Hannifin Corporation, and Machined Ceramics.

The Space Experiment Furnace (SEF) is a facility managed by the Consortium for Materials Development in Space (CMDS) based at the University of Alabama in Huntsville (UAH).

The initial objective of the SEF project was to provide a vapor transport furnace for use by the CCDS's. The SEF is not one furnace but three separate furnaces in one unit. The SEF was manufactured by Boeing Commercial Space Development Company, Seattle, WA, and is similar to Boeing's Crystal Transport Experiment (CVTE) furnace which flew in October 1992 on STS-52.

The SEF has room for two samples per furnace, for a total of six samples. The CVTE was designed as a middeck facility while the SEF is designed for flight in the SPACEHAB Space Research Laboratory. The first flight will be on SPACEHAB-2. The SEF has two transparent furnaces for operations at various temperatures up to approximately 900oC. The third furnace has an opaque core that reaches temperatures of 1080 degrees C.

The SEF differs from UAH's other furnace, ECLIPSE, in several ways. First, the SEF can process different type samples (materials), notably crystals grown from vapor. Second, the furnace processes the samples in transparent ampoules that can be watched and adjusted to optimize crystal growth. Third, the sample ampoules can be translated within the furnace to control the applied temperature gradients. And, fourth, while the opaque furnace can be used for metal and alloy processes, such as liquid metal sintering, it can provide temperature gradients as compared to the isothermal characteristics of ECLIPSE.

Thus, although the original CVTE furnace was designed to process crystals, the SEF is not restricted to crystals. For instance, on SPACEHAB-2, UAH used the opaque core for its Sintered and Alloyed Materials project, while Clarkson University, another CCDS, used a furnace with transparent cores for crystal growth.

The industry affiliates involved in designing, fabricating, and integrating the SEF for SPACEHAB-2 flight are: Boeing Commercial Space Development Company, Seattle, WA; McDonnell Douglas Aerospace - Huntsville, Huntsville, AL; and Wyle Laboratories, Huntsville, AL.

The Principal Investigator for the UAH/CMDS Sintered and Alloyed Materials project which used the opaque core furnace in the SEF for SPACEHAB-2 is Dr. James E. Smith, Jr., Associate Professor and Chairman, Department of Chemical and Materials Engineering, The University of Alabama in Huntsville. Dr. Smith is also the Principal Investigator of the ECLIPSE furnace experiment which was flown on SPACEHAB-2.