Differences of thermal decomposition behaviors and combustion properties between CL-20-based propellants and HMX-based solid propellants

2019 ◽  
Vol 140 (5) ◽  
pp. 2529-2540 ◽  
Author(s):  
Shuiping Zhou ◽  
Xiaoyang Zhou ◽  
Gen Tang ◽  
Xiang Guo ◽  
Aimin Pang
2021 ◽  
Author(s):  
Weimin Wang ◽  
Hui Li ◽  
Yanjing Yang ◽  
Fengqi Zhao ◽  
Heng Li ◽  
...  

Abstract Nano Al has always been the research hotspot in the field of energetic materials because of its high energy density and combustion temperature, and has been considered as a fuel to enhance the energy release of various propulsive systems. In this work, nanocomposite fibers were fabricated by electrospinning technology, in which nano Al and recrystallized RDX particles were integrated with NC fibers. The morphology and chemical components of NC/Al, NC/RDX, and NC/Al/RDX composite fibers were characterized by XRD, FT-IR, SEM, TEM and BET. The agglomeration of nano Al particles in fibers is significantly inhibited, and the recrystallized RDX and nano Al particles are uniformly dispersed in NC fibers, resulting in the rough surfaces of the composite fibers. The thermal analysis shows that nano NC fibers have lower thermal decomposition temperature (202.1 ℃) and apparent activation energy (149.32 kJ mol-1) than raw NC (208.2 ℃ and 218.5 kJ mol-1), and NC/Al/RDX exhibits improved thermal decomposition properties compared with NC/RDX and NC/Al. The laser ignition experiments suggest that the uniformly dispersed nano Al particles could obviously promote the combustion and shorten ignition delay time. However, RDX may delay ignition due to its high decomposition temperature, but can significantly enhance the combustion properties of NC/Al/RDX fibers. Among the all samples, the NC/Al/RDX (1:1:0.2) exhibits shortest ignition delay time and most violent combustion flames, which can be attributed to the fibrous structure and the enhanced heat and mass transfer between the components.


2021 ◽  
Vol 11 (20) ◽  
pp. 9392
Author(s):  
Haijun Zhang ◽  
Jianxin Nie ◽  
Gangling Jiao ◽  
Xing Xu ◽  
Shi Yan ◽  
...  

Ammonium perchlorate (AP) is a common oxidant in solid propellants, and its thermal decomposition characteristics at low temperatures (less than 240 °C) are key to the study of the thermal safety of propellants. Here, the low-temperature thermal decomposition characteristics of AP were investigated at 230 °C. The micromorphology of the low-temperature decomposition residues was characterized by scanning electron microscopy and 3D nano-computed tomography in order to analyse the evolution of microscopic pore structures, and the effect of the AP pore structure on combustion performance was then tested and analysed with a homemade closed bomb. The results demonstrate that the low-temperature decomposition of AP first occurs near the surface of the particles, simultaneously starting at multiple points and forming pores, and then gradually expands towards the interior until almost all of the pores connect with one other. Compared with ordinary AP, porous AP has a significantly improved combustion rate. When the ratio of porous AP to Al was 80:20, the peak pressure in the closed bomb was increased by 2.7 times; the rate of change in peak pressure increased 34 times, leading to a higher reaction speed and higher reaction intensity, and a typical explosion reaction occurred.


2018 ◽  
Vol 22 (4) ◽  
pp. 1665-1671 ◽  
Author(s):  
Yun-Bo Chen ◽  
Chun Liu ◽  
Shao-Li Zhang ◽  
Guo-Qiang Chen ◽  
Tie-Ling Xing

In order to obtain the flame retardant silk fabric, silica sols and phytic acid were prepared and applied to the silk fabrics. Vertical combustion experiment, thermogravimetric analysis, Fourier transform infrared spectra and smoke density test were used to investigate the combustion behavior, thermal property, and kinetics model of silk fabrics before and after flame retardant finish. The results showed that the sol coating on silk fabrics could increase the carbon residue and hinder the spread of flame when burning, and the tensile strength of treated silk was slightly damaged. Furthermore, the kinetics model of silk thermal decomposition conformed to Avrami-Erofeev model.


Author(s):  
Jing Shi ◽  
Xiangying Xing ◽  
Huixiang Wang ◽  
Lin Ge ◽  
Haizhen Sun ◽  
...  

The design and fabrication of efficient catalysts for ammonium perchlorate (AP) decomposition is crucial to the performance of composite solid propellants. Herein, a novel hierarchical structure material of Cu-WO3 nanowire...


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