Al–based Energetic Nanomaterials – Design, Manufacturing, Properties and Applications

<p>INTRODUCTION ix</p>
<p>ACKNOWLEDGEMENTS xi</p>
<p>CHAPTER 1. NANOSIZED ALUMINUM AS METAL FUEL 1</p>
<p>1.1. Al nanoparticles manufacturing 2</p>
<p>1.1.1. Vapor–phase condensation methods&nbsp;2</p>
<p>1.1.2. Wet chemistry 6</p>
<p>1.1.3. Mechanical methods 7</p>
<p>1.2. Example of Al nanoparticles passivation technique&nbsp;8</p>
<p>1.2.1. Metallic coating&nbsp;9</p>
<p>1.2.2. Organic coating&nbsp;9</p>
<p>1.3. Characterization of Al nanoparticles properties 11</p>
<p>1.3.1. Light scattering methods 12</p>
<p>1.3.2. Gas adsorption method: specific surface measurement, BET diameter 13</p>
<p>1.3.3. Thermal analysis: purity or aluminum content percentage and oxide thickness&nbsp;13</p>
<p>1.3.4. Chemical analysis 15</p>
<p>1.4. Oxidation of aluminum: basic chemistry and models&nbsp;16</p>
<p>1.4.1. Initial stage of aluminum oxidation from first principles calculations 16</p>
<p>1.4.2. Thermodynamic modeling of Al oxidation under low heating rate 18</p>
<p>1.5. Why incorporate Al nanoparticles into propellant and rocket technology? 23</p>
<p>1.5.1. Reduction of the melting point 24</p>
<p>1.5.2. Increase in the reactivity&nbsp;25</p>
<p>CHAPTER 2. APPLICATIONS: AL NANOPARTICLES IN GELLED PROPELLANTS AND SOLID FUELS 27</p>
<p>2.1. Gelled propellants 27</p>
<p>2.2. Solid propellants 29</p>
<p>2.3. Solid fuel 31</p>
<p>CHAPTER 3. APPLICATIONS OF AL NANOPARTICLES: NANOTHERMITES&nbsp;33</p>
<p>3.1. Method of preparation 35</p>
<p>3.1.1. Ultrasonic nanopowder mixing 36</p>
<p>3.1.2. Rapid expansion of a supercritical dispersion 38</p>
<p>3.1.3. Molecular self–assembly of nanoparticles&nbsp;39</p>
<p>3.2. Key parameters 42</p>
<p>3.2.1. The bulk density, theoretical density and compaction&nbsp;42</p>
<p>3.2.2. The stochiometry&nbsp;44</p>
<p>3.2.3. The size of Al and oxidizer particles&nbsp;46</p>
<p>3.2.4. The passivation layer 49</p>
<p>3.3. Pressure generation tests 50</p>
<p>3.4. Combustion tests 52</p>
<p>3.4.1. Open tray experiments 52</p>
<p>3.4.2. Optical temperature measurement: spectroscopy 53</p>
<p>3.4.3. Photodiodes 54</p>
<p>3.4.4. Confined combustion tests 54</p>
<p>3.5. Ignition tests&nbsp;56</p>
<p>3.5.1. Impact ignition 56</p>
<p>3.5.2. High–rate heating (106 107&deg;C/s) 57</p>
<p>3.5.3. Low and uniform heating (10 100&deg;C/s) 57</p>
<p>3.6. Electrostatic discharge (ESD) sensitivity tests&nbsp;58</p>
<p>CHAPTER 4. OTHER REACTIVE NANOMATERIALS AND NANOTHERMITE SYSTEMS 63</p>
<p>4.1. Sol gel materials 63</p>
<p>4.2. Reactive multilayered foils 66</p>
<p>4.2.1. Bimetallic multilayered foils 67</p>
<p>4.2.2. Thermite multilayered foils 72</p>
<p>4.2.3. Summary 77</p>
<p>4.3. Dense reactive materials&nbsp;77</p>
<p>4.3.1. Arrested reactive milling&nbsp;78</p>
<p>4.3.2. Cold–spray consolidation&nbsp;81</p>
<p>4.4. Core shell structures 83</p>
<p>4.5. Reactive porous silicon&nbsp;86</p>
<p>4.6. Other energetic systems&nbsp;88</p>
<p>CHAPTER 5. COMBUSTION AND PRESSURE GENERATION MECHANISMS 91</p>
<p>5.1. General views of Al particle combustion: micro versus nano, diffusion–based kinetics&nbsp;93</p>
<p>5.2. Stress in the oxide layer and shrinking core model 95</p>
<p>5.3. Aluminum oxidation through diffusion–reaction mechanisms&nbsp;97</p>
<p>5.4. Melt–dispersion mechanism&nbsp;99</p>
<p>5.5. Gas and pressure generation in nanothermites&nbsp;100</p>
<p>5.5.1. Thermodynamic models&nbsp;100</p>
<p>5.5.2. Application to Al/CuO 103</p>
<p>CHAPTER 6. APPLICATIONS 107</p>
<p>6.1. Reactive bonding 108</p>
<p>6.2. Microignition chips 110</p>
<p>6.3. Microactuation/propulsion 113</p>
<p>6.3.1. High energetic actuators&nbsp;113</p>
<p>6.3.2. Fast impulse nanothermite thrusters&nbsp;113</p>
<p>6.3.3. Smooth actuators&nbsp;116</p>
<p>6.4. Material processing and others 119</p>
<p>CONCLUSIONS&nbsp;121</p>
<p>BIBLIOGRAPHY 125</p>
<p>INDEX 149</p>