JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2019
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IF 4.029
Mo Yan,Xiaoming Duan,Zhuo Zhang,Xingqi Liao,Xichen Zhang,Baofu Qiu,Zengyan Wei,Peigang He,Jiancun Rao,Xiaodong Zhang,Dechang Jia,Yu Zhou
Ball milling was used on synthesized Cr 2 AlC powders, and dense Cr 2 AlC bulk ceramics with almost pure phase were fabricated by hot pressing these ball milled Cr 2 AlC powders at 1300 °C for 2 h under 30 MPa. The phase compositions and the microstructures of powders and bulk ceramics were characterized. The mechanical properties and dislocation analysis of bulk ceramics were also investigated. Our results indicated that the grain size of powders became uniform and smaller after ball milling, which was also inherited in the bulk ceramics. Moreover, the mechanical properties of hot pressed Cr 2 AlC ceramics, including flexural strength , fracture toughness, and Vickers hardness , significantly increased by using ball milled powders treated at speed 200 rpm. The organization of hexagonal dislocation networks during hot pressing and reduction of grain size both had a positive effect on improving mechanical properties.
研究领域:
材料科学
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陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
ULTRASONICS SONOCHEMISTRY
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2023
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IF 8.4
Monireh Alimohamadi,Alireza Khataee,Samira Arefi-Oskoui,Behrouz Vahid,Yasin Orooji,Yeojoon Yoon
This study aims to investigate the sonocatalytic activation of hydrogen peroxide (H 2 O 2 ) using Cr 2 AlC MAX phase prepared by the reactive sintering process. The hexagonal structure of the crystalline MAX phase was confirmed by X-ray diffraction. Moreover, the compacted layered structure of the MAX phase was observed via scanning electron microscopy and high-resolution transmission electron microscopy. Under the desired operating conditions, Cr 2 AlC MAX phase (0.75 g/L) showed suitable potential to activate H 2 O 2 (1 mmol/L) under sonication, thereby allowing a considerable removal efficiency for various organic pollutants, including dimethyl phthalate (69.1%), rifampin (94.5%), hydroxychloroquine (100%), and acid blue 7 (91.5%) with initial concentration of 15 mg/L within 120 min of treatment. Kinetic analysis proved that the degradation reaction followed pseudo-first-order kinetics. Scavenging tests demonstrated that hydroxyl radicals and singlet oxygen were effective species during degradation. Furthermore, a probable mechanism for dimethyl phthalate degradation was suggested according to gas chromatography-mass spectroscopy and nuclear magnetic resonance analyses. The obtained results confirmed the capability of the triple Cr 2 AlC/H 2 O 2 /US process as a promising method for treating contaminated water.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TRIBOLOGY INTERNATIONAL
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2023
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IF 6.2
Hongming Wei,Gangwen Feng,Xiaoya Li,Wenyi Zhan,Feiyang Li,Yanzhang Dai,Jianpeng Zou
Cu/graphite composites are widely used in various fields as friction materials . However, their tribological properties are limited by the inadequate wettability between Cu and graphite and the insufficient strength of the Cu matrix. To strengthen Cu/graphite composites and improve their interface bonding, this investigation employed Cr 2 AlC to modify Cu/graphite composites fabricated by spark plasma sintering (SPS). The microstructure, interface characteristics, and tribological properties of the composites were thoroughly examined. The results show that the composites exhibit favorable tribological properties, which improved with the increase in sintering temperature . Specifically, as the sintering temperature increases from 800 °C to 980 °C, the friction coefficient of the composites decreases from 0.170 to 0.138, while the wear rate decreases from 9.92 × 10 −7 mm 3 /N·m to 1.86 × 10 −7 mm 3 /N·m.
研究领域:
材料科学
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摩擦学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2022
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IF 5.532
Zetan Liu,Jingkun Xu,Xiaoqing Xi,Weijia Luo,Ji Zhou
Since the synthesis of non-oxidized ceramic and alloy powders requires both high temperature and oxygen insulation conditions, here we demonstrate a cost-efficient molten salt sealing/shielded synthesis method with dynamic gas tightness. Compared to conventional synthesis method, it can prevent the loss of reaction materials at high temperature, cut off the connection between reacting material and outside air, and does not require long-time ball milling mixing treatment or provision of applied pressing before or during heating. Only low-cost salts (e.g., NaCl, KCl), a few minutes of raw material mixing, and regular heating molds are required to obtain high-purity (>96 wt%), micron-sized Ti 3 AlC 2 and Ti 3 SiC 2 powders with narrow size distribution, which significantly decreased the complexity and production costs in the synthesis process. The effect of temperature and raw material content on the products were investigated. The mechanism of diffusion reaction between reactants in molten salt environment was analyzed. The new method developed here was also applicable to Ti 2 AlC, V 2 AlC and Cr 2 AlC MAX phases, as well as provided new ideas for the preparation of other MXenes precursors with certain stoichiometric ratios, air-sensitive materials and nanopowders .
研究领域:
材料科学
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化学工程
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纳米技术
✓ 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）