Electrophoretic assembly of Al/CuBi2O4 based-energetic films and the effect of destructive behavior with fuel/oxidant ratio

Physical destruction of microchips for data security based on thermite cannot simultaneously fulfill the demands of energy release and pressure output. Here, we have successfully assembled microchips based on Al/bimetallic oxide (CuBi2O4) energetic films through electrophoretic deposition. Al/CuBi2O4 exhibits excellent energy release and pressure output, the heat release of Al/CuBi2O4 is more concentrated, as extensive heat released by Al/CuO triggered the reaction of Al and Bi2O3, which will be conducive to the destructive behavior. The effects of fuel and oxide with different ratios on exothermic performance were systematically investigated, including heat release, ignition threshold energy, ignition mass loss rate and pressure release. The best fuel/oxide ratio on Al/ CuBi2O4 energetic films is found to be 5.06:1 through inductively coupled plasma atomic emission spectrometry. The distribution between Al fuel and CuBi2O4 rods is the most uniform at this ratio, hence it possesses the maximum heat release (926.4 J/g), lower ignition threshold (0.25 mJ), and faster pressurization rate (179.80 MPa/s). Importantly, high-speed photography results show that the intense reaction destroyed the energetic microchip (the thickness is about 0.3 mm) in only 10 ms.