Abstract Micrometer‐sized aluminum is widely used in energetics; however, performance of propellants, explosives, and pyrotechnics could be significantly improved if its ignition barriers disrupted. We report morphological, thermal, chemical characterization fuel rich aluminum‐polytetrafluoroethylene (70–30 wt‐%) reactive particles formed by high low energy milling. Average particle sizes range from 15–78 μm; specific surface areas approx. 2–7 m 2 g −1 due to milling induced voids cleaved...

An efficient approach that combines short-term (minutes) high-energy dry ball milling and wet grinding to tailor the nano- microstructure of Ni+Al composite reactive particles is reported. Varying ball-milling conditions allows control volume fraction two distinct milling-induced microstructures, is, coarse nanolaminated. It found increasing nanolaminated structure present in leads a decrease their ignition temperature (Tig) from 700 500 K. Material with also be more sensitive impact when...

In this paper, we report that the thermal conductivity (TC) of heat transfer nanofluids containing Ni coated single wall carbon nanotube can be enhanced by applied magnetic field. A reasonable explanation for these interesting results is nanotubes form aligned chains under field, which improves via increased contacts. On longer holding in gradually move and large clumps nanotubes, eventually decreases TC. When reduce field strength maintain a smaller right after TC reaches maximum, value...

We have developed a process for the synthesis of silver nanoparticles protected with passivating shell dodecylamine in toluene media using tin(II) acetate as reducing agent. Based on electrochemical series, during reduction Sn(II) oxidizes into Sn(IV) which reduces Ag(I) Ag(0). The nucleation and growth processes result particles diameters range 5–20 nm. This simple non-aqueous one pot can be easily scaled up to produce grams matter hours. also dispersed many solvents make them suitable...

Engineering reactive materials is an ever present goal in the energetics community. The desire to have configured such a manner that performance tailored and energy delivery can be targeted. Additive manufacturing (3‐D printing) one area could significantly improve our capabilities this area, if adequate formulations are developed. In paper, fluoropolymer based inks developed with micron (mAl) nanoscale aluminum (nAl) serving, as fuel at high solids loading (up 67 wt%) their viscosity...

Metal-based reactive composites have great potential as energetic materials due to their high energy densities and uses structural enhanced blast however these can be difficult ignite with typical particle size ranges. Recent work has shown that mechanical activation of powders increases ignition sensitivity, yet it is not fully understood how the role microstructure refinement duration will influence impact combustion behavior materials. In this work, compacted mechanically activated Ni/Al...

Abstract Sensitive nanoenergetic powders, such as nanothermites, have traditionally been processed by ultrasonic mixing of very low solids loaded suspensions in organic solvents, which has restricted their use and application due to high solvent content associated handling issues. In this work, we report on the performance quality nanothermite mixtures prepared a LabRAM resonant mixer at loadings compared mixing. Specifically, aluminum‐bismuth(III) oxide (Al/Bi 2 O 3 ) system polar N ,...

Abstract Double base propellants composed of nitrocellulose (NC) and nitroglycerine (NG) are widely used. However, the inclusion liquid NG presents both stability performance problems: may migrate from propellant in storage, it softens at high levels. In this work, novel nitrate ester 1,4‐dinitrato‐2,3‐dinitro‐2,3bis(nitratomethylene) butane (SMX) is considered as a replacement for double propellant. Thermochemical calculations indicate improved when compared with common JA2 SMX loadings...

The thermal and mechanical responses of a cyclotetramethylene-tetranitramine-based explosive (PBX 9501) two non-energetic mock materials (900-21 PBS under high-frequency excitation are presented. Direct contact ultrasound transducers were used to excite samples through frequency range 50 kHz 40 MHz. response each sample was approximated from receiving transducer trends confirmed via laser Doppler vibrometry. steady-state the measured at discrete frequencies infrared thermography. A maximum...

The development of smart energetics is at the forefront research community. desire to have that could ON/OFF capability, tunable performance, and/or targeted energy delivery. Therefore, efforts been focused on designing systems respond stimuli in a controlled manner. In this paper, nanoscale aluminum (nAl)/fluoropolymer reactive are studied and piezoelectric nature fluoropolymers used as means sensitize system. Using capacitor type setup, drawing our previous efforts, three fluoropolymer/nAl...

Silicon-based nanoenergetics have great potential due to silicon's good thermochemical properties, high active content, and surface modification potential. The combustion characteristics of several silicon-based were studied by performing equilibrium calculations, initial screening tests, instrumented burn tube experiments. Results constant pressure calculations predicting adiabatic temperatures volumetric gas production are shown the mechanisms that produce these results discussed. For 14...

Abstract Microwave frequency electromagnetic properties are critical for understanding and predicting the heating ignition behavior of explosives subjected to microwave irradiation. In this work we report relative complex permittivity measurements in X‐band (8–12 GHz) 13 neat measured by circular cavity technique. This data set was then used conjunction with COMSOL 4.3 Multiphysics ® finite element analysis software design simulate a low power (100 W), high electric field applicator. The...

Abstract Nanothermites are a promising replacement energetic for many devices but their use has been limited by high sensitivity during processing, hazardous processing solvents, and time consuming deposition. Incorporating deposition into single step, especially if no organic solvents were used, could allow nanothermites to be applied safely in wider range of applications. This work reports on the performance characterization direct‐deposited water processed nanothermite inks semiconductor...

Abstract Due to its thin passivation layer, potentially good aging characteristics, and ease of surface functionalization nanoscale silicon (Si) may offer some advantages over nanoaluminum as a reactive fuel in nanoenergetic compositions, particularly with fluorine‐based oxidizers. Currently, Si nanopowder can be quite expensive the quality commercial powders has been found vary drastically. As result limited efforts have focused on role specific area, active content, morphology, dominant...