Defence Technology
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2024
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IF 5
Zhanjun Yang,Hao Liu,Li Mi,Xiaoqian Wang,Oisik Das,Zhong xuan Han,Lin Jiang
To investigate the differences in combustion and energy release characteristics of metastable intermolecular composite materials composed of aluminum alloys and polyvinylidene fluoride (PVDF) with different compositions, two types of alloys were selected: Al-Mg and Al-Si. Pure aluminum powder of the same size was also chosen for comparison. The PVDF-coated metal particle composites and the mixtures of PVDF with metal particles were prepared using electrospray (ES) and physical blending methods (PM), respectively. A systematic study was conducted on the morphology, compositional structure, combustion performance, energy release characteristics, and thermal reactivity of the fabricated composites and their combustion products through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), combustion performance experiments, closed vessel pressure tests, and simultaneous thermogravimetric-differential scanning calorimetry (TG-DSC). The experimental results indicated that the PVDF-coated metal particles prepared by the electrospray method exhibited a distinct core-shell structure, with the metal particles in close contact with the PVDF matrix. Compared to the PM blended materials, the ES composites demonstrated superior combustion performance and energy release characteristics during combustion. Analysis of different metal fuel systems under identical preparation conditions revealed that Al-Mg and Al-Si fuels modulate the combustion and energy release properties of aluminum alloy-PVDF MICs through two distinct pathways.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2022
·Vol. 11
·期 3
·1351-1360
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IF 14.511
Deqi Wang,Jie Liu,Tianyu Tan,Shishuo Liu,Guozhen Xu,Zhimiao Zhang,Yang Qin,Fengsheng Li
Boron (B) is the most suitable fuel for rocket ramjet. However, boron oxide (B2O3) on the surface of B causes many problems in its application. B2O3 cross-links with hydroxyl prepolymer, which reduces the processibility of the system. Moreover, B2O3 hinders contact between the oxidation component and internal active B. Consequently, B is difficult to ignite, and its reactivity and combustion efficiency are limited. To solve these problems, a dual-core–shell structure, B@LiF@AP, B embedded with LiF as core and AP as shell, has been designed and prepared. Its multi-effect synergies, improving processibility, protecting B from oxidation by AP before burning, decomposing B2O3, and improving reactivity and combustion efficiency, have been confirmed. Compared with the mixed sample of B and AP (B–AP), the heat release of B@LiF@AP increased by 211.10%. The combustion efficiency of B@LiF@AP increased by 42.60% more than that of B@AP. The ignition test showed that its ignition energy was reduced by 37.89% and the flame temperature increased by 26.27% than that of B–AP. The application and development of boron-based rocket ramjet will be accelerated because the application problems of B are solved by B@LiF@AP.
研究领域:
材料科学
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航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2024
·Vol. 11
·期 7
·076520
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IF 1.8
Yuanhang Fang,Tingbian Zhan,Xiaojun Li,Changyou Xie,Xinggao Zhang,Weizhan Wang,Xiansong Jiang
A W-Zr alloy doped with ceramic powder W54.5Zr35-xNi6.7Fe3.3Mo0.5 (ZrO2) x was prepared by powder metallurgy. The effects of the ceramic content on the dynamic and static compressive mechanical behavior and energy release properties of the alloy were studied. The results showed that the addition of ceramics enhanced the energy release characteristics of the W-Zr alloy, and made the alloy break more thoroughly and the fragment cloud distribute evenly. The reaction delay time was shorter and the energy release reaction was more complete. However, the maximum temperature of the alloy reaction decreased. In addition, the addition of ceramics improves the mechanical properties of the material, and its compressive strength is much higher than that of traditional W-Zr alloys.(ZrO2)1 exhibited good mechanical behavior and energy release characteristics. The aftereffect damage performance was further verified using a ballistic gun experiment. Ballistic gun test results showed that (ZrO2) 1 can penetrate A92124 aluminum targets with a thickness of 2 mm at a speed of 809.3 m s−1 and ignite post-target absorbent cotton, with both penetration and post-target damage capabilities.
研究领域:
材料科学
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力学
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能源材料
✓ 已验证
DOI
高影响因子
ACTA ASTRONAUTICA
·
2015
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IF 1.122
Daolun Liang,Jianzhong Liu,Jinwu Xiao,Jianfei Xi,Yang Wang,Yanwei Zhang,Junhu Zhou
The microstructure of amorphous boron and the primary combustion products of boron-based fuel-rich propellant (hereafter referred to as primary combustion products) was analyzed by scanning electron microscope . Composition analysis of the primary combustion products was carried out by X-ray diffraction and X-ray photoelectron spectroscopy. The energy release properties of amorphous boron and the primary combustion products were comparatively studied by laser ignition experimental system and thermogravimetry–differential scanning calorimetry. The primary combustion products contain B, C, Mg, Al, B 4 C, B 13 C 2 , BN, B 2 O 3 , NH 4 Cl, H 2 O, and so on. The energy release properties of primary combustion products are different from amorphous boron, significantly. The full-time spectral intensity of primary combustion products at a wavelength of 580 nm is ~2% lower than that of amorphous boron. The maximum spectral intensity of the former at full wave is ~5% higher than that of the latter. The ignition delay time of primary combustion products is ~150 ms shorter than that of amorphous boron, and the self-sustaining combustion time of the former is ~200 ms longer than that of the latter. The thermal oxidation process of amorphous boron involves water evaporation (weight loss) and boron oxidation (weight gain). The thermal oxidation process of primary combustion products involves two additional steps: NH 4 Cl decomposition (weight loss) and carbon oxidation (weight loss). CL-20 shows better combustion-supporting effect than KClO 4 in both the laser ignition experiments and the thermal oxidation experiments.
研究领域:
材料科学
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燃烧学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Xiang Ke,Xiang Zhou,Gaozi Hao,Lei Xiao,Jie Liu,Wei Jiang
One of the challenges for the application of energetic materials is their energy-retaining capabilities after long-term storage. In this study, we report a facile method to fabricate superhydrophobic Al/Fe 2 O 3 nanothermite film by combining electrophoretic deposition and surface modification technologies. Different concentrations of dispersion solvents and additives are investigated to optimize the deposition parameters. Meanwhile, the dependence of deposition rates on nanoparticle concentrations is also studied. The surface morphology and chemical composition are characterized by field-emission scanning electron microscopy, X-ray diffraction, X-ray energy-dispersive spectroscopy, and X-ray photoelectron spectroscopy. A static contact angles as high as 156° shows the superhydrophobicity of the nanothermite film. Natural and accelerated aging tests are performed and the thermal behavior is analyzed. Thermal analysis shows that the surface modification contributes to significantly improved energy-release characteristics for both fresh and aged samples, which is supposed to be attributed to the preignition reaction between Al 2 O 3 shell and FAS-17. Superhydrophobic Al/Fe 2 O 3 nanothermite film exhibits excellent long-time storage stability with 83.4% of energy left in natural aging test and 60.5% in accelerated aging test. This study is instructive to the practical applications of nanothermites, especially in highly humid environment.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Defence Technology
·
2021
·
IF 3.172
Fuwei Li,Yue-ting Wang,Cheng-ai Wang,Yun Shen,Ze-hua Zhang,Jian Cheng,Shuang-zhang Wu,Ying-hua Ye,Rui-qi Shen
The core-shell metastable intermolecular composites (MIC) have attracted much attention in the past few years due to their unique properties. Here, the preparation of Al-Core heterojunction fibers using PVP as a template is proposed. The nano-Al was directly added to the precursor solution of cupric acetate monohydrate (CAM)/Polyvinylpyrrolidone (PVP), and the initial Al@CAM/PVP fibers were obtained via electrospinning. The core-shell MIC fibers are then obtained by calcining the initial fibers. The morphology, structure, and composition of Al-core MIC fibers were characterized, that the energetic fibers calcined at 300 °C, 350 °C, and 400 °C have a core-shell structure with shell compositions Cu x O and PVP, Cu x O and CuO, respectively. The energy release characteristics of Al-core MIC were investigated, and preliminary ignition tests were performed using an ignition temperature measuring instrument and a pulsed laser. The energetic fibers calcined at 300 °C exhibited unique properties. The decomposition of PVP in the shell layer promoted exotherm, and a low-temperature exothermic peak was shown at 372–458 °C. Lower ignition temperatures and higher flame heights were observed in the combustion tests than calcination at 350 °C and 400 °C. An unexpected result was that PVP can play a positive role in Al/CuO nanothermites. Simultaneously, this preparation method provided an idea for the integrated preparation of core-shell Al-Core MIC fibers and tuning the properties of MIC.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）