FORMATION OF CONSOLIDATED NANOTHERMITE MATERIALS USING SUPPORT SUBSTRATES AND/OR BINDER MATERIALS

摘要

Consolidated nanothermite felts with reduced sensitivity to electrostatic discharge for safer handling were produced without a significant reduction of the nanothermite reactivity. A polyester felt material with a thickness of 1.65 mm was easily infiltrated with a nanothermite slurry and the dried felt material prevented small particles from breaking off during handling. Combustion of 100 mg of the dried felt nanothermite in a closed-volume pressure cell generated higher pressure than those generated by nanothermite granules produced using a similar water-based processing method. The nanothermite felts also effectively absorbed nitrocellulose as a gasifying agent without a significant decrease in reaction rate. High-density reactive composites, based on tantalum metal fuel with a specific gravity of 16.6 and nanoscale Bi_2O_3 oxidizer, were formed with densities in excess of 5.0 g/cm~3. THV 220A, a fluorocarbon polymer with oxidizing properties, was used as an effective binder in the composite. These materials were combined in acetone with tetrafluoroethylene, hexafluoropropylene, and vinylidene (THV), and after drying were pressed into pellets. Combustion of an 800-mg pellet lasted 5 s and was accompanied by the formation and ejection of hot particles from the surface of the pellet. Differential scanning calorimetry analysis determined that the ignition of the high-density composite occurs below 620 K, which is lower than common in nanothermite systems.