JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Pei Zhang,Yu Zuo,Guochao Nie
Microarc oxidation films on 2024 aluminium alloy were prepared in sodium silicate-based electrolyte with α-Al 2 O 3, SiC, TiO 2 , ZrO 2 and CeO 2 nanoparticles . The effects of oxide nanoparticles on the pore parameters and the properties of the films were studied. EDS and XRD analysis showed that the nanoparticles partly entered the film, probably by the combination effects of embedding and melting. The porosity of the microarc oxidation films prepared in electrolytes with nanoparticles increased to some extent. With the addition of the different nanoparticles, the film porosity increased from 9.6% to 21.6%, the bonding strength of the films to the adhesives increased from 12.3 MPa to 22.8 MPa, and the film microhardness decreased from 785.7 HV to 564.2 HV. Particularly, the microhardness of the film prepared with SiC nanoparticles was as high as 1063.5 HV. The addition of all the nanoparticles into the electrolytes did not affect the thermal cracking resistance of the films. EIS measurements showed that after 1440 h immersion in NaCl solution the resistance of the microarc oxidation films prepared in electrolyte with nanoparticles was still much higher than that of the original film, and the film capacity increased slowly. Among the nanoparticles, TiO 2 and CeO 2 showed the best effect to increase the corrosion resistance . Weight loss test results showed that the corrosion rate of the films prepared with TiO 2 and CeO 2 nanoparticles was only about one third of the original film after 8640 h immersion. The good corrosion resistance of the microarc oxidation films may depend mainly on the good shielding property of the inner compact layer.
研究领域:
材料科学
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2022
·
IF 3.752
Yang WANG,Qiang LIU,Biao ZHANG,Hao-qian ZHANG,Yi-cheng JIN,Zhao-xin ZHONG,Jian YE,Yu-han REN,Feng YE,Wen WANG
To address the issue that B 4 C ceramics are difficult to be wetted by aluminum metals in the composites, TiB 2 was introduced via an in-situ reaction between TiH 2 and B 4 C to regulate their wettability and interfacial bonding. By pressure infiltration of the molten alloy into the freeze-cast porous ceramic skeleton, the 2024Al/B 4 C–TiB 2 composites with a laminate-reticular hierarchical structure were produced. Compared with 2024Al/B 4 C composite, adding initial TiH 2 improved the flexural strength and valid fracture toughness from (484±27) to (665±30) MPa and (19.3±1.5) to (32.7±1.8) MPa·m 1/2 , respectively. This exceptional damage resistance ability was derived from multiple extrinsic toughening mechanisms including uncracked-ligament bridging, crack branching, crack propagation and crack blunting, and more importantly, the fracture model transition from single to multiple crack propagation. This strategy opens a pathway for improving the wettability and interfacial bonding of Al/B 4 C composites, and thus produces nacre-inspired materials with optimized damage tolerance.
研究领域:
材料科学
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力学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
·
2023
·Vol. 33
·期 4
·1862-1873
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IF 2.3
Yan Huanyuan,Liu Wensheng,Ma Yunzhu,Wang Tao,Wu Lei,Yang Lun,Tang Siwei
In this work, Al 2 O 3 ceramic coatings were prepared the surface of powder metallurgy (PM) 2024 aluminum alloy via the micro-arc oxidation (MAO) technique. The effects of the current density and the oxidation treatment time on the microstructure and properties of the MAO coatings were investigated. The results reveal that the oxide film mainly comprises the γ-Al 2 O 3 phase, the amorphous Al 2 O 3 phase, and a small amount of the mullite phase. There are traces of W in the coatings, which exist in the form of W, WO 3 , and W 18 O 49 . With increasing current density, the thickness and surface roughness of the MAO coatings prepared on the PM 2024 alloy increase, while their surface hardness first increases and then decreases. The increase in the current density promotes the transformation of the amorphous Al 2 O 3 phase into the γ-Al 2 O 3 phase. The maximum hardness value of 1270 HV is obtained at a current density of 20 A dm −2 . The MAO coatings provide superior corrosion protection for the PM 2024 aluminum alloy, and the MAO coatings obtained at a current density of 15 A dm −2 exhibit the highest corrosion resistance.
研究领域:
材料科学
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表面工程
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陶瓷涂层
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腐蚀防护
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铝合金
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Tongyuan Meng,Zeen Wang,Gui Wang,Bo Li,Ying Xu,Haiying Zhao,Xinhui Gao,Zhaoxin Zhong,Zhanhong Chen,Yang Wang,Yushi Qi,Futian Liu
Bidirectional freeze casting combined with pressure infiltration has demonstrated significant potential as an effective approach for fabricating bioinspired lamellar composites with excellent strength and toughness. However, their dynamic mechanical response remains underexplored. In this study, B 4 C/2024Al composites with long-range ordered nacre-like architectures were fabricated using bidirectional freeze casting followed by pressure infiltration. The mechanical properties and deformation behavior under both quasi-static and dynamic compression conditions were systematically investigated. The results reveal that dynamic compressive strength and strain were significantly higher than their quasi-static counterparts, largely attributed to strain rate hardening and localized matrix melting. Compared to unidirectionally structured composites, the bidirectionally structured ones exhibited superior mechanical performance, achieving a maximum compressive strength of 1088.6 MPa at a strain rate of 3000 s −1 (40 vol% B 4 C/2024Al composite). A clear dependence of flow stress and energy absorption capability on B 4 C volume fraction was observed. As B 4 C content increased, the compressive strength rose, but dynamic strain energy density showed a decreasing trend beyond 20 vol% due to reduced ductility. Specifically, the energy density peaked at 133.08 MJ/m 3 for the 20 vol% composite and declined with further ceramic addition, indicating a trade-off between strength and impact energy absorption. The enhanced toughness under dynamic loading is primarily attributed to adiabatic shear localization in the aluminum matrix, which facilitates localized softening and strain accommodation. Additional contributions include crack deflection and branching within the hard ceramic layers, as well as plastic deformation and thermal softening-induced toughening mechanisms in the metallic phase. These findings highlight the promise of nacre-inspired B 4 C/Al composites for advanced lightweight armor systems, offering an optimized balance between strength, toughness, and energy absorption under high-strain-rate loading.
研究领域:
材料科学
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机械工程
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复合材料
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仿生材料
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动态力学行为
✓ 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）