SURFACE & COATINGS TECHNOLOGY
·
2021
·
IF 4.158
Xiaoli Feng,Haifeng Wang,Xuechao Liu,Canming Wang,Hongzhi Cui,Qiang Song,Kun Huang,Neng Li,Xue Jiang
Inconel 625 + x Al ( x = 0, 2.5, 5.0, 7.5, 10.0) alloy coatings were prepared by laser cladding. The addition of Al promoted the formation of the BCC phase, which changed the coating microstructure from an FCC + δ phase + Laves phase to FCC + BCC + δ phase + Laves phase. Inconel 625 + 2.5 Al alloy showed the greatest corrosion resistance among all samples. The formation of an Al 2 O 3 film improved the corrosion resistance of the coating, but excess Al decreased the Cr 2 O 3 content in the film, which decreased the corrosion resistance of the coating. Increasing the Al content aggravated the lattice distortion and improved the solid solution strengthening effect, while also increasing the amount of BCC phase, which improved the coating hardness. After adding Al, the Inconel 625 + x Al alloy coatings displayed strong plastic deformation resistance, and their wear resistance was improved due to the presence of a hard phase.
研究领域:
材料科学
·
表面工程
✓ 已验证
DOI
高影响因子
Energetic Materials Frontiers
·
2022
·
IF 0
Hua Fang,Jin-qiang Zhou,Peng Deng,Peng-fei Zhu,Xue-yong Guo
To understand the thermal decomposition and combustion characteristics of HMX/aluminum (Al) composites, this study prepared the HMX/Al composites with different Al contents and carried out the thermal decomposition and combustion performance tests of these composites. The thermal analysis results showed that the activation energy of the HMX/Al composites increased from 483.94 kJ·mol −1 to 541.60 kJ·mol −1 when the Al content increased from 0 to 30 wt%. However, the change in the Al content had little effect on the heat flow of the HMX/Al composites. The combustion results showed that the calorific value of HMX/Al-30 composite reached 16,860 J·g −1 . The flame height and burning intensity gradually increased with an increase in the Al content, and the burning duration of HMX/Al-10, HMX/Al-20, and HMX/Al-30 gradually decreased by 0.21, 0.57 ms and 0.91 ms, respectively. The results showed that Al powder as metal fuel can control the combustion reactions and energy output of HMX-based explosives.
研究领域:
化学
·
材料科学
✓ 已验证
DOI
COMBUSTION AND FLAME
·
2020
·
IF 4.57
Qianqian He,Jun Wang,Yaofeng Mao,Huamo Yin,Wei Cao,Fude Nie
The incorporation of aluminum (Al) into explosives represents a facility and efficient way to enhance the energy output through the secondary reaction between Al and the detonation products of explosive. The Al/O ratio and microstructure of HMX/Al play critical roles in combustion performance and energy output. Herein, a gradient structured HMX/Al composite has been designed and fabricated via 3D printing technology using well-dispersed HMX/Al-based ink. For HMX/Al lines, the second reaction heat increases from 196.5 J/g to 1644.8 J/g and the burning rate would decrease from 14.6 to 12.0 mm/s with Al content increased from 10 to 30 wt%. For gradient structured HMX/Al, the burning rate could be controlled by varying the component ratio and the burning rate of each component in the gradient structure was higher than that of the normal HMX/Al counterpart. Furthermore, a gradient evolution of pressure output was monitored for gradient structured HMX/Al cylinder ignited by the laser. These results indicate that the gradient structure as an effective approach can tune combustion performance and energy output of HMX/Al.
研究领域:
材料科学
·
燃烧与爆炸学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
MengXue Xiong,Min Yang,QianLin Chen,TingYa Cai
Bauxite residue contains a certain amount of alkali metal ions, among which sodium ions are predominant and have a great impact on its application performance. In this paper, a series of sodium ion adsorbents with different Al contents were prepared based on the structural characteristics of NASICON-type materials to study the effect on sodium ion adsorption and regeneration adsorption performance. The results showed that the adsorbent with 40% Al had the best adsorption rate (95.6%). The adsorbents were characterized by SEM, XRD, Raman spectroscopy , TG-DSC, XPS and N 2 adsorption-desorption, and the results showed that the adsorbents had a stable three-dimensional network structure. The adsorption isotherm models, adsorption kinetics and adsorption thermodynamics were discussed. The adsorption process followed the Langmuir isotherm model and pseudo-second-order kinetic model and was a spontaneous exothermic reaction . In addition, the adsorption mechanism was also discussed; this mechanism involved the participation of carbon-oxygen bonds and electrostatic interactions during adsorption. Desorption and regeneration experiments demonstrated that the adsorbent had excellent reusability, with an adsorption rate of 88.82% after three cycles. This study effectively solves the problem of sodium ion disposal in waste liquid after bauxite residue dealkalization to a certain extent, alleviating the environmental pollution caused by subsequent waste liquid discharge. Additionally, the later application of sodium ions can "turn trash into treasure". This study not only provides a new route for the separation of sodium ions in bauxite residue but also has great significance both from an environmental perspective and from a resource recovery perspective.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2024
·
IF 6.3
Liuxin Wang,Sijie Liu,Renda Wang,Shuai Xu,Chunmei Wen,Fangfang Ge,Mengyu Gao,Yang Si,Sizhe Diao,Bingsheng Li
Solar salts have a high energy storage density, and using solar thermal power generation technology can provide humanity with long-term, stable, and low-cost electricity. However, severe corrosion of structural materials when in contact with molten chloride salts is one of the main challenges limiting their long-term service at high temperatures. In this study, two types of aluminium-containing austenitic (AFA) stainless steels: 18Ni and 25Ni AFA steels, were prepared and their corrosion behavior in molten chloride salt (NaCl-MgCl₂-KCl with 30.2–47.1–22.7 mol.%) at 700 °C over different durations (200, 400, 600, and 800 h) was investigated. The corrosion products, thickness of the corrosion layer, and microstructure were characterized in detail. The effects of alloying elements on enhancing resistance to molten chloride salt corrosion were studied. Both types of AFA steels exhibited significant dissolution and oxidation behavior during the corrosion process, and the aggregation of Laves phases was observed. The corrosion depth after 800 h was found to reach a maximum of 131.3 μm, significantly lower than conventional 304 stainless steels under similar conditions. Why AFA steels exhibit resistance to chloride salt corrosion is discussed. The findings provide valuable guidance for the development of structural materials suitable for high-temperature molten chloride salt applications.
研究领域:
材料科学
·
腐蚀工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·
IF 2.7
Wu Yang,Wenhao Liu,Mengze Zheng,Cong Zhu,Tianqi Li,Yunjun Luo
A polyol bonding agent (BA) was utilized to enhance the mechanical properties of propellant with low aluminum content. Through scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) analysis, it was discovered that BA can physically bond to the surfaces of ammonium perchlorate (AP) and hexogen (RDX). The results of mechanical testing showed that the use of BA can significantly improve the mechanical properties of propellants. Specifically, as the amount of BA increases, the maximum tensile strength ( σ m ) of the propellant also increases, the fracture elongation ( ε b ) initially increases and then decreases, the “dewetting ratio” continuously decreases, and the creep resistance of the propellant also increases. At a BA content of 0.2%, the σ m of the propellant reaches 0.6 MPa, the ε b exceeds 50%, and the “dewetting ratio” is less than 1.1.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2020
·
IF 5.289
Deqing Zhu,Yuxiao Xue,Jian Pan,Congcong Yang,Zhengqi Guo,Hongyu Tian,Dingzheng Wang,Yue Shi
The alumina content of iron ores for sintering is gradually increasing with the growing depletion of high-grade iron ores, which is harmful to the sintering process. Therefore, it is essential to reveal the action mechanism of alumina on sinter quality. In this paper, the aluminum occurrence of various iron ores was determined by applying X-ray diffraction (XRD), optical microscopy, scanning electron microscopy and energy dispersive spectrum analysis (SEM-EDS). Then, the effects of iron ore type, aluminum occurrence (free alumina, gibbsite, diaspore, alumogoethite and kaolinite) and alumina content on formation characteristics of SFCA bonding phases as well as sinter matrix strength were investigated based on laboratory compact sintering tests. The results show that the discrepancy of aluminum occurrence contributes to different SFCA formation characteristics and then sinter matrix strength, due to different reactivity of various aluminum-containing minerals with iron oxides and fluxes. Increasing alumina content generally results in an increase in the porosity of sinters and deterioration of sinter matrix strength for all aluminum occurrence. Aluminum in the form of kaolinite is more conducive to form dendritic or acicular SFCA with superior sinter matrix strength compared with other aluminum occurrences. In contrast, aluminum occurring in free alumina presents greatest adverse impacts on sinter matrix strength due to its poor reactivity and high porosity of resultant sinters.
研究领域:
冶金工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2024
·
IF 4.7
Hui-chuan REN,Xiao-bo MIN,Yong KE,Long-gong XIA,Yun-yan WANG,Cong PENG,Yun LI,Rong-he TAN,Chuan-fu ZHANG
A method to upgrade the iron grade in copper slag was proposed using lime to decompose Al 2 O 3 -containing fayalite melt (AFMT). Thermodynamic calculations indicated that adjusting the CaO/AFMT ratio can yield a residual melt with a FeO concentration of 75-88 wt.% and produce Ca 2 SiO 4 . In-situ observations suggested that the reaction was impeded in some way. Quenching experiments revealed that the initial reaction products consisted of calcium ferrite compounds and FeO-CaO melt. At the FeO-CaO melt/AFMT interface, Ca 2 SiO 4 particles precipitated, forming a dense Ca 2 SiO 4 film that significantly impeded mass transfer. Although trace amounts of Al 2 O 3 in AFMT temporarily enhanced mass transfer, they were insufficient to overcome this retardation effect. The decomposition reaction was far from achieving equilibrium, demonstrating a self-retardation effect. Measures must be implemented to eliminate this self-retardation effect and enhance the efficiency of reaction kinetics.
研究领域:
冶金工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2022
·
IF 4.778
Hongdan Wu,Xiaodi Liu,Xuexin Liu,Jinhua Zhang,Jishun Yu
Magnesium alumina spinel solid solutions with different chemical compositions were synthesized and their crystal structures were refined using the Rietveld method based on synchrotron radiation X-ray diffraction (XRD). A linear relationship between the lattice parameters a 0 and x in Mg 1- x Al 2+2/3 x □ 1/3 x O 4 was established, the thermal stability and lattice thermal expansion of the solid solutions by in-situ high temperature XRD were investigated. Alumina was eliminated from the high-solubility alumina-rich spinel solid solution to form corundum and a lower-solubility alumina-rich spinel solid solution. The relationship between a 0 and temperature is expressed by a quadratic polynomial. The thermal conductivity of Mg 1- x Al 2+2/3 x □ 1/3 x O 4 decreased almost linearly with an increase in x , which is attributed to the stronger point-defect scattering effect induced by the difference in atomic mass and cation radii and the increase in cation vacancies as alumina dissolves in spinel.
研究领域:
材料科学
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF AOAC INTERNATIONAL
·
2019
·Vol. 98
·期 1
·225-229
·
IF 1.201
Zhang Jing,Yong Xiaojing,Zhao Dongyan,Shi Qiuyi
The content of mononuclear Al (Ala%) changed with its determination time (ta) under different dosages of Ferron (7-iodo-8-hydroxyquinoline-5-sulfonic acid, [Ferron]), and the change of Ala% with [Ferron] at different ta was systematically investigated for the firsttime. Thus, the most appropriate ta was found with the optimal [Ferron]. Also, the judgment of the platform (flat or level portion) of the complete reaction on the absorption-time curve determined in the hydroxyl polyaluminum solution by Ferron timed spectrophotometry (Ferron assay) was first digitized. The time point (tb) of complete reaction between the medium polyaluminum (Alb)and Ferron reagent depended on the reaction extent, and time could not be used only to judge. Thus, the tb was accurately determined and reduced
to half of original, which improved the experiment efficiency significantly. The Ferron assay was completely optimized.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2018
·
IF 0
Rong Chen,Kai Qu,Jiawei Li,Penghui Zhu,Chenlong Duan,Jing Zhang,Xiwen Li,Xiao Liu,Zhijian Yang
The stability of aluminum (Al) nanoparticles is a key issue that determines the energy performance of solid fuels, Al-based green propellants, and fuel cells. The surface native oxide shell (Al2O3), nevertheless, cannot stabilize Al nanoparticles under hot water conditions. Herein, we report a passivation method utilizing an ultrathin zirconia (ZrO2) coating via atomic layer deposition, where a sub-nanometer coating layer could completely prevent the reactions between Al nanoparticles and hot water (80 °C). The weight percentage of metallic Al for ultrathin ZrO2 coated Al nanoparticles can reach 82.2 wt %, which is close to that of original Al nanoparticles with Al2O3 native oxide (88 wt %). The metallic Al’s weight has been kept at 93.4% for the ultrathin ZrO2 coated Al nanoparticles compared to the original Al nanoparticles. As a comparison, the Al2O3 coated Al nanoparticles result in the oxidation failure in 60 °C water. The proposed passivation mechanism is attributed to ZrO2 coating’s structural stability and the enhanced hydrophobicity to water. The ultrathin ZrO2 passivation offers a valuable tool for enhancing the stability of Al nanoparticles and thereby enables their potential applications in energy field.
研究领域:
材料科学
·
纳米技术
·
能源材料
·
表面工程
·
无机化学
✓ 已验证
DOI
INORGANIC CHEMISTRY
·
2022
·
IF 5.436
Yixiong Deng,Jiayu Zhou,Gen Li,Honghai Liu,Xionghou Gao,Yuanyuan Yue,Haiyan Li,Fangming Xie,Hongtao Liu
SBA-15 has recently emerged as a potential material for the catalytic conversion of large molecules. Usually, SBA-15 has a low content of aluminum due to the conventional acidic synthesis medium. Although a few approaches have been adopted to prepare Al–SBA-15 with a high alumina content, it is still challenging to prepare well-ordered Al–SBA-15 with a high alumina content. Here, we demonstrate a facile synthesis process in neutral mediums for the grafting of Al into the framework of SBA-15. This approach relies mainly on the dissociation of Si–O–Si bonds and the polymerization of Si–O–Si/Al bonds promoted by sodium persulfate (SPS) in neutral mediums. In this way, well-ordered Al–SBA-15 with a high aluminum content and enhanced acidity was obtained. Results of X-ray fluorescence spectroscopy (XRF) showed an n(SiO2)/n(Al2O3) ratio of 13.7, much lower than that of the conventional sample (21.7) obtained in acidic medium. The characterization results indicated the presence of a well-ordered Al-containing mesophase with high hydrothermal stability. Notably, the Al content and the acidity of Al–SBA-15 can be tuned by changing the SPS amount.
研究领域:
材料科学
·
化学工程
·
催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）