Xifeng Lu Qilong Wang Deliang Cui
材料科学技术（英文）
g-C3N4/TiO2 composite were prepared by hydrolysis of Ti(OC4Hn 9 )4 and the precursors of g-C3N4 at room temperature and annealing in nitrogen atmosphere. X-ray diffraction results revealed that all the products were anatase structure. The chemical nature of O, N of the g-C3N4/TiO2 were identified by X-ray photoelectron spectroscopy, presenting N-Ti-O and N-Ti-N doping status of the composite. The g-C3N4/TiO2 composite showed better photocatalytic activity for the UV and visible-light degradation of Rhodamine B.
关键词:
Composite materials
,
Chemical synthesis
,
X-ray photoelectron spectroscopy (XPS)
V. Arumugam
金属学报(英文版)
Acoustic emission (AE) can be used for in situ structural health monitoring of the composite laminates. One of the main issues of AE is to characterize different damage mechanisms from the detected AE signals. In the present work, pure resin and GFRP composites laminates with different stacking sequences such as 0°, 90°, angle ply[±45°], cross-ply [0°/90°] are used to trigger different failure mechanisms when subjected to tensile test with AE monitoring. The study of failure mechanisms is facilitated by the choice of different oriented specimens in which one or two such mechanisms predominate. Range of peak frequencies in each orientation is investigated using FFT analysis. Fast Fourier Transform (FFT) enabled calculating the frequency content of each damage mechanism. Randomly selected hits from each range of peak frequencies for the specimens with different orientations subjected to tensile test with AE monitoring are analyzed using short time FFT (STFFT) analysis. STFFT analysis is used to highlight the possible failure mechanism associated with each signal. The predominance of failure modes in each orientation is useful in the study of discrimination of failure modes in composite laminates from AE data.
关键词:
Composite materials
王志平
,
梁吉勇
,
张国尚
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2014.02.007
对采用不同台阶比率挖补修理的玻璃纤维增强树脂基复合材料层合板进行了吸湿实验,获得了各种台阶比率试样的吸湿规律以及损伤行为.通过面内剪切强度测试以及形貌观察,研究分析了导致吸湿试件强度降低以及层间开裂的主要因素.实验发现:玻璃纤维增强树脂基复合材料的孔隙率是影响层合板吸湿率和层间开裂的重要影响因素,孔隙率越高,吸湿率越高,但层间开裂倾向却降低;台阶比率对长时间吸湿试件的强度保持率有较大的影响,恰当选择台阶比率不但有助于提高强度恢复率,还可减小因吸湿而产生的强度降低幅度;吸湿会导致玻璃纤维增强树脂基复合材料层合板的面内剪切强度大幅度下降,导致这种结果主要原因之一是吸湿会严重劣化纤维/树脂界面粘结状态.
关键词:
复合材料
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修补
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吸湿
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裂纹
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孔隙
曹利
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蒋持平
,
姚忠凯
,
雷廷权
金属学报
在备有拉伸台的扫描电子显微镜上原位观察了V_f为22％的碳化硅晶须增强铝(SiC_W/Al)复合材料压铸态试样和T_6态试样的动态拉伸过程。结果发现外加应力达到180-190MPa时复合材料内部就已形成许多微裂纹,裂纹一般在晶须端部形成,其扩展亦有一定的规律。经过对复合材料简化模型的复变函数分析和计算,求出了晶须周围应力场,进一步通过塑性力学的分析,从理论上解释了本文所观察到的实验现象。
关键词:
复合材料
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fracture
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stress distribution
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SiC whiskers
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aluminum
曲江英
,
李雨佳
,
李传鹏
,
石琳
,
邵光华
,
高峰
新型炭材料
以改进的Hummers法所制氧化石墨烯/硫酸锰( GO/MnSO4)悬浊液为原料,原位合成GO/MnO2复合物,再经低温热处理制备还原氧化石墨烯/Mn3 O4( rGO/Mn3 O4)纳米复合材料。通过改变GO/MnSO4悬浊液中MnSO4的质量含量实现rGO/Mn3 O4复合物中Mn3 O4质量分数的可控调变。该法充分利用氧化石墨烯原液中的锰离子,可节省原料,同时可避免氧化石墨烯繁琐的分离过程并简化实验步骤。所得复合材料作为超级电容器电极材料展现良好的电化学电容性能,在饱和K2 SO4电解质溶液和50 mA·g-1的电流密度下,Mn3 O4质量含量为88%时其比电容达284 F·g-1。
关键词:
石墨烯
,
四氧化三锰
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绿色合成
,
复合材料
,
超级电容器
刘良威
,
刘锦
,
李志慧
,
朱军
宇航材料工艺
叙述了某型号卫星碳纤维复合材料桁架胶接装配过程的配套条件、工艺方法和质量控制等内容.研究表明,杆件和接头的配合间隙介于0.1～0.3 mm时胶接强度较高；桁架的精度完全依靠高精度胶接工装保证,且最终精度能控制在0.2mm之内；合适的工艺方法和质量控制方法,能够满足碳纤维桁架结构的高精度和胶接质量要求,并且这些方法具有通用性.
关键词:
碳纤维
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复合材料
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卫星
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桁架
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装配
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胶黏剂
