MAGNESIUM COMPOSITES FOR REUSABLE HYDROGEN STORAGE MODULES

A PROPRIETARY APPROACH TO USING MAGNESIUM COMPOSITES FOR FABRICATING REUSABLE HYDROGEN STORAGE MODULES FOR THE NATIONAL AEROSPACE PLANE (NASP), THE X-30, IS PRESENTED. THESE HYDRIDE MATERIALS HAVE THE INHERENT CAPABILITY FOR STORING HYDROGEN AT ROOM TEMPERATURE TO DENSITIES NEARLY TWICE THAT OF LIQUID HYDROGEN. PRELIMINARY EXPERIMENTS INDICATE THAT THESE MAGNESIUM COMPOSITES CAN MAINTAIN THEIR STRUCTURALINTEGRITY OVER MANY ABSORPTION/DESORPTION CYCLES WITH CONSIDERABLY ENHANCED KINETICS AS COMPARED TO BULK MAGNESIUM AND ITS ALLOYS. SUCH COMPOSITES, BECAUSE THEY DO NOT POWDER ON HYDRIDING, HAVE SIGNIFICANT ADVANTAGES OVER OTHER KNOWN HYDRIDES, NAMELY: 1) ENHANCED THERMAL CONDUCTIVITY BY ORDERS OF MAGNITUDE; 2) RAPID DESORPTION CAN BE ACHIEVED BY ELECTRICAL HEATING OF THE COMPOSITE RODS, THUS FACILITATING COMPUTER CONTROL OF THE POWER DENSITY AVAILABLE; AND 3) SINCE THE ELECTRICAL RESISTANCE OF A COMPOSITE ROD IS A FUNCTION OF ITS HYDROGEN CONCENTRATION, ONE CAN CONTINUOUSLY MONITOR THE FUEL REMAINING IN A ROD BY MEASURING ITS RESISTANCE. THIS NEW MAGNESIUM COMPOSITE TECHNOLOGY HAS THE POTENTIAL FOR MAKING AN IMPORTANT CONTRIBUTION TO THE DEVELOPMENT OF THE NASP-X-30.