Advanced Rocket Propulsion Technologies

This Phase I SBIR research proposal will investigate the feasibility of a continuous high flux source of boron vapor for preparing B/para H2 cryosolids for HEDM research. The boron source apparatus will be designed for the preparation of 5 mol% B/pH2solids at rates sufficient to form transparent material and for integration with the cryo-solid spectroscopy apparatus at AFRL. The proposed approach involves free evaporation of pure boron atoms from a thin layer of liquid boron in a high vacuumenvironment. The liquid boron, formed by CO2 laser beam heating and superheated at its surface, will coexist with an underlying layer of solid boron that supports the liquid. Research objectives are to (i) demonstrate the purification of boron usingcontainerless processing of liquid boron, for use in the vapor source, (ii) fabricate a test chamber for vaporization experiments, (iii) perform experiments to determine the operating conditions to obtain a stable, continuous, known and well-controlledintense boron vapor flux, and (iv) develop the design for the apparatus to be developed in Phase II. In Phase II, we would develop and deliver the high flux boron vapor source to AFRL for use in the Air Force's HEDM research program.The R&D will benefitthe Air Force HEDM research program by satisfying a key issue of the Cryogenic HEDM Solid Prospectus. It will open markets for CRI in advanced systems to conduct research on cryo-solid HEDM. It will provide the means to supply, for the first time,ultra-pure elemental boron, as a solid element and as a vapor for vapor deposition applications, in Dual-Use R&D markets.