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新型电力电子器件封装用导热胶粘剂的研究 总被引:11,自引:0,他引:11
通过在环氧树脂中加入不同量的具有高导热系数的填料(氧化铝、氮化铝、碳化硅),并研究加入填料后环氧树脂的导热性能随填料填充体积分数的变化规律,研制出了具有高导热能力的新型导热胶粘剂。 相似文献
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环氧树脂等高分子聚合物材料热导率低,长期使用时,存在热导致的故障和绝缘失效等隐患.通过向环氧树脂中填充具有高导热性和高绝缘性的微米氮化硼和纳米氧化铝填料制备高导热复合绝缘材料,研究填料填充量及配比对复合材料导热性能和绝缘性能的影响.结果表明:当总填充量为30%,微米h-BN与纳米A12O3的质量比为3∶1时,复合材料的热导率、击穿时间和复介电常数虚部ε"分别为1.182 0W/(m·K)、31.9 s和0.034,比环氧树脂分别提升了697%、21.4%和406%,且复合材料在高频高压电场下具有良好的耐受性能. 相似文献
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以不饱和聚酯改性环氧树脂为基体,采用硅烷偶联剂表面改性后的金刚石、碳化硅和氧化铝微粉为填料分别制备高导热绝缘漆,分析3种填料对绝缘漆的防沉淀性、导热系数、击穿电压和粘度的影响,采用3种改性填料复合制备了一种高导热绝缘漆,并在低压电机的整机上进行应用试验。结果表明:加入未改性填料的绝缘漆易产生沉淀现象,而加入硅烷偶联剂表面改性填料的绝缘漆储存稳定性好,不易沉淀;添加改性后的金刚石、碳化硅和氧化铝微粉填料后的绝缘漆,其导热系数随微粉含量的增加均有所提高、电气强度随微粉含量的增加而降低、粘度随微粉含量的增加而增大;3种改性填料复合使用制备的高导热绝缘漆导热系数可达0.432W/(m·K),粘度69 s,电气强度23.4 MV/m。电机温升同比下降7 K,电机效率提高0.97%。 相似文献
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采用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)对氮化硼纳米片(BNNS)进行表面改性,然后将其掺入环氧树脂基体中,制备了环氧树脂/功能化氮化硼纳米片(EP/BNNS-KH560)复合材料。对功能化氮化硼纳米片的结构及形貌进行测定,并对EP/BNNS-KH560复合材料的性能进行研究。结果表明:BNNS表面成功接枝KH560,在透射电子显微镜下展现出透明薄层结构;宽能级间隙的BNNS-KH560填料的加入可以保持复合材料的高电绝缘性、优异的介电性能和力学性能,使其热稳定性提高,并能在环氧树脂基体中形成良好的导热通道,有效改善复合材料的导热性能。当复合材料中BNNS-KH560质量分数为20%时,复合材料的导热系数可达到0.51 W/(m·K)。 相似文献
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随着先进电子及高频通信技术的发展,聚酰亚胺薄膜作为重要的聚合物绝缘材料面临越来越高的导热性能要求.传统聚酰亚胺薄膜的本征导热系数较低,无法满足电子元器件的快速散热需求.近年来,研究人员对导热聚酰亚胺薄膜材料开展了大量研究,通过加入无机导热填料获得了具有良好导热性能的聚酰亚胺基复合薄膜.本文综述了国内外在导热聚酰亚胺绝缘薄膜材料方面的最新研究进展,详细讨论了聚酰亚胺/导热填料复合薄膜的导热行为,系统阐述了导热性能的影响因素,包括填料类型、尺寸、加入量、填料与基体的界面相互作用等,并对高性能聚酰亚胺基导热绝缘薄膜材料面临的技术挑战进行了总结与展望. 相似文献
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液晶环氧树脂导热性能较差,耐热性不够高,使得电力、电子器件运行过程中散热困难,温度升高导致环氧树脂绝缘发生劣化,大大影响了电力、电子器件的使用可靠性和寿命。该文开发了制备高取向度液晶环氧纤维薄膜的静电纺丝方法和工艺,结合真空抽滤方法向纤维薄膜中填充纳米氮化硼(nano boron nitride,BNNSs),进一步制备了填充取向型纳米氮化硼/液晶环氧纤维复合导热薄膜,研究了液晶环氧纤维直径和BNNSs填充浓度对BNNSs/液晶环氧树脂导热复合薄膜的导热性能和交流击穿强度的影响规律。结果表明:液晶环氧树脂纤维薄膜的面内热导率随着纤维直径的减小而增大,当纤维直径减小至280 nm时,热导率为0.699 W/(m·K);当填充BNNSs导热填料后,BNNSs/液晶环氧树脂导热复合薄膜的面内热导率随填料浓度增大而急剧上升,在填充量为15%时可以达到5.88 W/(m·K),比280 nm直径的纯薄膜提高了779%。同时发现,液晶环氧树脂纤维薄膜在直径较细的情况下交流击穿强度较高,280 nm纤维薄膜的击穿强度为26.55 kV/mm,BNNSs导热填料的添加可以减小薄膜复合材料的热击穿,填充... 相似文献
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Konzelmann S. Hoffmann C. Merte R. Peier D. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2008,15(2):327-333
Epoxy resin compounds are manufactured with silica glass and aluminum nitride as filling material at various filling ratios. The thermal conductivity and electrical properties, like dielectric loss or electric strength, are measured and compared as regards to an utilization as electrical insulator. 相似文献
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Experimental results on charge storage and discharge in double layers of silicon dioxide and silicon nitride will be reported and discussed. SiO2 with a thickness of 300 nm was thermally grown on silicon wafers, while cover layers of Si3N4 with thicknesses of 50, 100, and 150 nm were deposited chemically at atmospheric pressure. The samples were charged by the point-to-grid corona method. At room temperature, the measured surface potential V was stable during a period of almost three years. Isothermal measurements under different environmental conditions showed an improved charge retention compared to a single layer grown silicon dioxide. After ~3 h at 300°C, the observed voltage drop was <10% for the double layers and ~60% for bare SiO2. Similar results were obtained under a humid condition of 95%RH and 60°C. Besides, thermally stimulated current (TSC) was measured in setup with a temperature ramp of 200°C/h. For the double layers, a current peak with a maximum temperature at ~500°C was observed. The measured current in the range of 300 to 400°C, the location of current maxima observed in thermally grown silicon dioxide or APCVD silicon nitride, was negligible. In addition to improved electret properties the internal stress in the investigated double layers can be adjusted by a proper thickness ratio of oxide layer to nitride layer. Therefore double layers of silicon dioxide and nitride seem to be promising materials for integrated sensors and actuators based on the electret effect 相似文献
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多胶云母带广泛应用于大型高压电机的主绝缘材料,其导热性直接影响到空冷电机的温升及绝缘的可靠性。采用保护热流计法导热仪、浸渍法密度计研究了目前应用比较成熟的多胶云母带粘合剂的热传导性能及其与密度的关系。结果表明:酚类固化体系的导热系数明显高于TOA体系和桐马体系;酚类固化体系中引入TOA增韧后降低了固化物的导热系数;导热系数与密度存在一定的关系,密度较大的固化物其导热系数一般也较大。 相似文献
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Jinkuk Kim Jejun Park Ji Hwa Hong Sung Jin Choi Gi Hwan Kang Gwon Jong Yu Nam Soo Kim Hee-eun Song 《Journal of Electroceramics》2013,30(1-2):41-45
Anti-reflection coating (ARC) film effectively reduces the reflection of sunlight on the silicon wafer surface and then increases substantially the solar cell conversion efficiency. In this work, we carried out experiments to lessen the reflectance and thus improve the conversion efficiency with double AR coating layer with silicon nitride and silicon oxide by plasma enhanced chemical vapor deposition (PECVD) for the silicon solar cells. The optimized thicknesses and refractive indices of each ARC layer were calculated with Essential Macleod program and the theoretical method. The single antireflection layer of silicon nitride was applied with 800 Å thickness and its cell showed the conversion efficiency as 17.45 %. For the double layer AR coating (DLARC), silicon nitride layer was deposited first using SiH4 and NH3, and then, silicon oxide was deposited with SiH4 and N2O. The thicknesses of SiNx and SiO2 were 800 Å and 1400 Å for DLARC-1 and 500 Å and 1000 Å for DLARC-2, respectively. As a result, the reflectance of DLARCs was lower than single SiNx and then yielded increase of short-circuit current and conversion efficiency. The completed solar cell with DLARCs showed conversion efficiencies of 17.57 % for DLARC-1 and 17.76 % for DLARC-2. This indicates that the double AR coating layer is effective to obtain the high efficiency solar cell with PECVD. 相似文献
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Makarova M. Gong Y. Cheng S-.L. Nishi Y. Yerci S. Li R. Negro L. D. Vu?kovi? J. 《IEEE journal of selected topics in quantum electronics》2010,16(1):132-140
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Electricdouble layercapacitor(EDLC )isauniqueelectro chemicalenergystoragedevicewhichexhibitsmuchgreatercapaci tancethanconventionalcapacitors Italsooffersmuchhigherpow erdensitythanconventionalbatteries (C2 H5) 4 NBF4 PCisfre quentlyusedaselectrolyteinEDLCsforitsrelativelyhighelectro chemicalandthermalstability[1-2 ] However ,theconductivityof(C2 H5) 4 NBF4 PCisratherlowandtheviscosityisquitehigh AcetonitrilehasahighconductivityandhasalreadybeenusedassolventintheEuropeanmarketforcap… 相似文献