Combustion characteristics of nanoenergetic materials composed of aluminum, nickel oxide and a fluoroelastomer
This research work focuses on studying the combustion characteristics, specifically the burning rates of nanoenergetic materials composed of nano aluminum and nickel oxide. A fluoroelastomer, FC-2175 (chemically the same as Viton™), was used as the binder. Nano aluminum and nickel oxide were chosen as this system is close to a gasless system, does not require pre-heating and has the potential for studying the effects of doping and magnetic field. Various parameters influence the combustion of these composites. Variation of burning rate with particle-size of the oxidizer, binder content, packing density and pressure were studied. The effect of doping the oxidizer and the presence of magnetic field on the burning rate were also studied. The burning rate was found to increase with decrease in particle-size but for smaller particles, specific surface area seemed to be the dominating factor affecting the burning rate. At larger particle-sizes, the results show that the particle-size is the dominating factor affecting the burning rate. The burning rate was also found to decrease with increase in binder content. Similarly, decreasing the pressure increased the burning rate. With increase in packing density, the results show that for this composite, the burning rate first increases and then decreases. This is likely due to the effect of convective and non-planar burning. To study the effect of doping, the oxidizer was doped with lithium (p-doping) and chromium (n-doping). Experiments depicted that doping may affect the burning rate. However, the variation in burning rate was also influenced by other factors like surface area and particle-size of the oxidizer, which varied in this experiment. The doped and undoped oxidizers had different particle-sizes and surface area and due to this, it is unclear if the trend in burning rate for these composites was due to the effect of doping or particle-size and surface area. As nickel is ferromagnetic, the effect of magnetic field on burning rate was explored. It was found that in the presence of a magnetic field, the burning rate decreased but a stronger magnetic field would be required to achieve a clear picture and arrive at a definite conclusion.
0548: Mechanical engineering