Publication

Abstract : A bench-scale shock tube apparatus has been employed to measure the velocity and intensity of pressure waves produced by the combustion of nanothermite materials, synthesized in our laboratory. The combustion wave speed of these novel materials ranges from 1500 m/s to 2400 m/s for a combination of CuO nanorod and nano-Aluminum with optimized sizes and a proper equivalence ratio. The highest speed is achieved by the process of self-assembly between the fuel and oxidizer. The lowest speed corresponds to simple physical mixture of oxidizer and fuel. In both cases, we observed generation of shockwaves, the strongest one resulting in the self-assembled case. Small quantities of nanothermites (10-200mg) were loaded into a cylindrical volume, and placed against an air-filled tube. Pressure transducers were mounted along the length of the tube to record pressure profiles at various positions. Using time-of-arrival analysis the velocity of the pressure wave was calculated. Mach numbers ranging from 1.1-3.5 were measured for various compositions of CuO-Al nanothermite. This system has been used to study the effect of nanothermite mass on the shock waves and compare different variations of nanothermite composites. This technique allows rapid testing for tuning of nanothermite compositions for shock wave applications in the defense, energy and biomedical fields.