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1.
《Journal of the European Ceramic Society》2020,40(4):1496-1504
In this study, Al2O3 workpieces were vacuum brazed by using Ni-45Ti binary alloy. The interfacial microstructure evolution of the joints obtained at different brazing temperatures was investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The bonding strength of the joints was measured by shear testing. The results indicated that Ni2Ti4O and AlNi2Ti were the main reaction products in the joint areas. Moreover, the Ti2Ni intermetallic compound formed in the brazing seam. The typical layer structure of the brazed joints was Al2O3/AlNi2Ti/Ni2Ti4O/Ti2Ni + NiTi/Ni2Ti4O/AlNi2Ti/Al2O3. With the brazing temperature increasing, the thickness of the Ni2Ti4O reaction layer adjacent to the Al2O3 substrate increased significantly, while the AlNi2Ti phase had a tendency to dissolve with the brazing temperature increasing. The mechanism for the microstructure evolution was also discussed. The maximum shear strength of 125.63±4.87 MPa of the joints was obtained when brazed at 1350 °C for 30min. The fracture occurred hardly in the interface between Al2O3 and Ni-45Ti filler alloy. 相似文献
2.
选用填料塔对草酸生产过程中产生的氮氧化物进行吸收处理。对填料塔本体进行了设计计算,结合已有的工程设计经验给出了确定填料塔本体尺寸的具体步骤,并讨论了设计应考虑的主要问题。所采用的工艺有效地降低了生产过程中氮氧化物的排放,降低了生产成本,减少了环境污染。 相似文献
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冯晓明 《中国材料科技与设备》2012,(4):1-4
本文介绍了商品超细氢氧化铝阻燃填料的应用、供需现状及目前的主要生产商和生产工艺,并对部分产品的特点进行了分析研究。 相似文献
5.
Nanocomposite polymer electrolytes (NCPEs) were prepared by blending poly (vinylidene fluoride-co-hexafluoro propylene) copolymer (PVdF-HFP) and polyethylene oxide (PEO) polymers and incorporation of ZnO inorganic nanofiller (PVdF-HFP:PEO:EC:PC:NaI:I2:ZnO). The highest ionic conductivity value of 8.36 mS cm−1 was recorded when 3 wt.% of ZnO inorganic nanofiller was incorporated into the NCPE system. Temperature-dependant ionic conductivity behaviour of NCPEs was analysed and proven to follow the Arrhenius thermal activated model. Structural studies of NCPEs were carried out using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy analysis. NCPEs were used to fabricate Dye-sensitized solar cells (DSSCs). Enhancements in the solar light to electricity conversion efficiency (η) of DSSCs were observed in the presence of ZnO inorganic nanofiller in the NCPE system and NCPE with 3 wt.% ZnO represented the highest η of 7.33% under full sun irradiation. 相似文献
6.
《国际聚合物材料杂志》2012,61(1-4):295-300
Abstract In poly(methyl methacrylate) and polyvinylpirrolydone the influence of aerosil on the kinetics of macroradical transformation at 120–220 K is established. The effect of filler is explained by the changes of the structural–physical properties of the polymer binder transformed into the interface state. From the kinetic data the effective thickness of interfaces is estimated. 相似文献
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文章通过介绍复合材料中无机填料的分散,填料表面处理,分散设备技术应用等内容,阐述了填料分散技术在覆铜板制造的应用。 相似文献
9.
《Microelectronics Journal》2014,45(12):1726-1733
This paper elucidates the thermal behavior of an LED employing metal filled polymer matrix as thermal interface material (TIM) for an enhanced heat dissipation characteristic. Highly thermal conductive aluminum (Al) particles were incorporated in bisphenol A diglycidylether (DGEBA) epoxy matrix to study the effect of filler to polymer ratio on the thermal performance of high power LEDs. The curing behavior of DGEBA was studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The dispersion nature of the Al fillers in polymer matrix was verified with Field Emission Scanning Electron Microscope (FESEM). The thermal performance of synthesized Al filled polymer composite as TIM was tested with an LED employing thermal transient measurement technique. Comparing the filler to polymer ratio, the rise in junction temperature for 60 wt% Al filled composite was higher by 11.1 °C than 50 wt% Al filled composite at cured state. Observed also from the structure function analysis that the total thermal resistance was 10.96 K/W higher for 60 wt% Al filled composite compared to 50 wt% Al filled composite. On the other hand, a significant rise of 9.5 °C in the junction temperature between cured and uncured samples of 50 wt% Al filled polymer TIM was observed and hence the importance of curing process of metal filled polymer composite for effective heat dissipation is discussed extensively in this work. 相似文献
10.
关键词识别是语音识别中的一个重要研究方向,而维吾尔语的关键词识别研究刚刚开始.结合维吾尔语音节特点和考虑影响关键词识别因素,提出在HMM模型的基础上对非关键词建立垃圾模型的方法,来提高关键词的识别效率。 相似文献