A route combining powder metallurgy and subsequent friction stir processing was utilized to fabricate carbon nanotube （CNT） reinforced AI （CNT/AI） and 6061AI （CNT/6061AI） composites. Microstructural observations...A route combining powder metallurgy and subsequent friction stir processing was utilized to fabricate carbon nanotube （CNT） reinforced AI （CNT/AI） and 6061AI （CNT/6061AI） composites. Microstructural observations indicated that CNTs were uniformly dispersed in the matrix in both CNT/AI and CNT/6061AI composites. Mg and Si elements tended to segregate at CNT-AI interfaces in the CNT/6061AI composite during artificial aging treatment. The tensile properties of both the AI and 6061AI were increased by CNT incorporation. The electrical conductivity of CNT/AI was decreased by CNT addition, while CNT/6061AI exhibited an increase in electrical conductivity due to the Mg and Si segregation.展开更多
To develop suitable sealants for intermediate temperature solid oxide fuel cells （IT-SOFC）, glass-ceramics based on the CaO-BaO-B203-AI203-Si02 system were studied. Coefficient of thermal expansion （CTE）, glass tr...To develop suitable sealants for intermediate temperature solid oxide fuel cells （IT-SOFC）, glass-ceramics based on the CaO-BaO-B203-AI203-Si02 system were studied. Coefficient of thermal expansion （CTE）, glass transition temperature （Tg） and dilatometric softening point temperature （Td） of specimens were determined by means of dilatometer analysis and crystallization temperature was measured by differential thermal analysis （DTA）. Also, crystallization behavior during prolonged heat-treatment and microstructure properties were studied by means of X-ray diffraction （XRD） and scanning electron microscopy （SEM）, respectively. Electrical properties were measured at different temperatures, and the results showed a high resistance （〉104 Ω） at the SOFC operation temperature （600-800 ℃）. Moreover, mechanical properties of heat-treated specimens （1, 10, 30, 50 h） were measured, Microstructure investigation revealed a well-adhered bonding between the sealant glass-ceramic electrolyte and glass.展开更多
为研究硅橡胶材料的老化特征,分别选取全新未运行、正常运行提前退役和运行中发生故障的220 k V硅橡胶电缆接头,通过测量凝胶含量和傅里叶红外光谱研究接头绝缘材料的微观结构变化;并对其拉伸和抗撕裂强度等力学性能,以及相对介电常数...为研究硅橡胶材料的老化特征,分别选取全新未运行、正常运行提前退役和运行中发生故障的220 k V硅橡胶电缆接头,通过测量凝胶含量和傅里叶红外光谱研究接头绝缘材料的微观结构变化;并对其拉伸和抗撕裂强度等力学性能,以及相对介电常数、介质损耗因数、体积电阻率和电气强度等电气性能进行测试分析。结果表明:在电、热、力老化或接头故障产生的短时高温作用下,硅橡胶绝缘的交联网络受到一定程度的破坏,从而使拉伸强度降低,断裂伸长率升高,同时体积电阻率明显下降。相较全新试样,退役试样和故障试样的绝缘-半导电界面撕裂强度均有所下降。运行状态对绝缘材料的介电强度没有显著的影响。展开更多
基金the support of the National Basic Research Program,China(Grant Nos.2011CB932603 and 2012CB619600)the National Natural Science Foundation, China(Grant No.51331008)
文摘A route combining powder metallurgy and subsequent friction stir processing was utilized to fabricate carbon nanotube （CNT） reinforced AI （CNT/AI） and 6061AI （CNT/6061AI） composites. Microstructural observations indicated that CNTs were uniformly dispersed in the matrix in both CNT/AI and CNT/6061AI composites. Mg and Si elements tended to segregate at CNT-AI interfaces in the CNT/6061AI composite during artificial aging treatment. The tensile properties of both the AI and 6061AI were increased by CNT incorporation. The electrical conductivity of CNT/AI was decreased by CNT addition, while CNT/6061AI exhibited an increase in electrical conductivity due to the Mg and Si segregation.
文摘To develop suitable sealants for intermediate temperature solid oxide fuel cells （IT-SOFC）, glass-ceramics based on the CaO-BaO-B203-AI203-Si02 system were studied. Coefficient of thermal expansion （CTE）, glass transition temperature （Tg） and dilatometric softening point temperature （Td） of specimens were determined by means of dilatometer analysis and crystallization temperature was measured by differential thermal analysis （DTA）. Also, crystallization behavior during prolonged heat-treatment and microstructure properties were studied by means of X-ray diffraction （XRD） and scanning electron microscopy （SEM）, respectively. Electrical properties were measured at different temperatures, and the results showed a high resistance （〉104 Ω） at the SOFC operation temperature （600-800 ℃）. Moreover, mechanical properties of heat-treated specimens （1, 10, 30, 50 h） were measured, Microstructure investigation revealed a well-adhered bonding between the sealant glass-ceramic electrolyte and glass.
文摘为研究硅橡胶材料的老化特征,分别选取全新未运行、正常运行提前退役和运行中发生故障的220 k V硅橡胶电缆接头,通过测量凝胶含量和傅里叶红外光谱研究接头绝缘材料的微观结构变化;并对其拉伸和抗撕裂强度等力学性能,以及相对介电常数、介质损耗因数、体积电阻率和电气强度等电气性能进行测试分析。结果表明:在电、热、力老化或接头故障产生的短时高温作用下,硅橡胶绝缘的交联网络受到一定程度的破坏,从而使拉伸强度降低,断裂伸长率升高,同时体积电阻率明显下降。相较全新试样,退役试样和故障试样的绝缘-半导电界面撕裂强度均有所下降。运行状态对绝缘材料的介电强度没有显著的影响。
