Results 71 to 80 of about 1,056 (155)
烧结温度对掺杂B2O3的SnO2压敏电阻微观结构和电气特性的影响
Dianci bileiqi, 2023 研究了不同的烧结温度对掺杂B2O3的SnO2压敏电阻的影响。通过电子扫瞄显微镜SEM图和X射线衍射图，对样品的内部结构进行了微观表征；测试了不同温度下SnO2压敏电阻样品小电流区的伏安特性曲线。实验结果表明，烧结温度为1 325℃,SnO2压敏电阻样品的晶粒尺寸比较均匀；样品表现出最佳的电气参数：泄漏电流为18.93μA/cm2,非线性系数为28.93,电压梯度为378 V/mm。
杨兴, 赵洪峰, 吴宇航, 谢清云
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Characterization of mechanical properties and primary investigation of pyrolysis and sintering of polycarbosilane-derived continuous fibers [PDF]
, 2005 Hi-NicalonSiC纤维是通过先驱体法制备并已商品化的高性能连续纤维，是制备耐高温SiC/SiC复合材料的关键原材料。降低纤维中氧的含量可提高其高温使用性能，而降低纤维的直径、减少缺陷可提高其力学性能。本论文主要对Hi-NicalonSiC纤维的力学性能进行系统表征并对PCS制备连续SiC纤维的烧成工艺进行初步探索。对Hi-NicalonSiC纤维的研究结果表明：①纤维的强度服从Weibull分布；纤维的模量服从正态分布；纤维的应变服从正态分布；纤维的直径分布服从正态分布。②Hi ...
吴清良
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Preparation of high-density iron soft magnetic materials by HVC technology [PDF]
, 2016 High density green compacts of annealed iron powder with a density of 7.70 g·cm-3 were prepared by high velocity compaction(HVC) combined with powder annealing.
DONG Guo-qiang +5 more
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Gaoya dianqi, 2000 本文总结和分析了ＣｕＣｒ真空开关触头材料的含气量、晶粒尺寸、致密度及成分均匀分布等微观特性对其分断能力、耐压性能、截流值等宏现性能的影响，并简要分析了现有的一些工艺方法，为真空开关ＣｕＣｒ触头材料的研究开发和应用提供参考。
修士新, 邹积岩, 何俊佳
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Influence of Cold Drawing Strain on Torsion Properties of 304H Steel Wire
Teshugang, 2021 The influence of structure evolution and defects of 304H stainless steel wire during the cold drawing process from Φ2.6 mm to Φ0.89 mm on torsion performance of stainless steel wire are studied.
彭科, 刘静, 袁泽喜, 彭志贤
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Crystalline Structures and Characterizations of Porous Silicon [PDF]
, 2009 The formation of porous silicon (PSi) involves the transition from perfect monocrystalline silicon to non-perfect crystalline such as polycrystalline or even amorphous structures, depending strongly upon the fabrication conditions and the nature of ...
Cheng, Xuan +3 more
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Preparation and mechanical properties of refractory metal carbide reinforced tungsten‒rhenium alloys [PDF]
Metal carbide doped tungsten‒rhenium alloys were prepared by the traditional pressureless sintering method. The effects of ZrC, TiC, and HfC metal carbides on the microstructures and mechanical properties of tungsten‒rhenium alloys were studied, and the ...
CHEN Fuge +5 more
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Dianci bileiqi采用传统的SnO2+CoO+Nb2O5+Cr2O3压敏电阻体系，深入研究了MgO掺杂对SnO2基压敏电阻综合电性能和微观形貌的影响。结果表明，当MgO掺杂量为0.5%(摩尔分数)可获得最佳的电性能，非线性系数为32，电压梯度为284.3 V/mm，漏电流为7.1 μA。这是因为Mg2+作为受主掺杂剂，提高了表面态密度，当MgO的掺杂量超过SnO2样品的溶解度极限时，在晶界处形成尖晶石，由于钉扎效应阻止了ZnO晶粒的生长，因此晶粒尺寸减小并形成更多晶界，有效提高了SnO2压敏电阻的综合电性能 ...
孙岩 +6 more
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Preparation and Magnetic Properties of NFC Ferrite sheets with High Permeability and Low Magnetic Loss Via Aqueous Tape Casting [PDF]
, 2015 近距离无线通讯（NFC）技术在最近几年发展迅速，与移动设备尤其是与手机的结合，将会极大地促进NFC技术的发展。移动设备上NFC功能的顺利实现，需要解决的硬件问题是制备一种高磁导率、低损耗的烧结铁氧体片。本论文采用固相反应法制备预烧铁氧体粉末，通过水基流延成型工艺制备铁氧体坯片，研究工艺条件、助熔剂及D离子对铁氧体片的烧结密度、微观形貌和磁学性能等的影响。通过工艺、成分和成型工艺的组合调整，制备出满足NFC功能使用的高磁导率、低磁损耗、高截止频率、厚度较薄且具有较好磁导率温度稳定性的烧结铁氧体膜片。 首先，
马腾
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Dianci bileiqi, 2008 采用溶液添加法在中压压敏电阻中引入金属K+离子,研究不同含量的K+对ZnO压敏电阻电性能的影响及其机理,结果表明:K+能增强ZnO压敏电阻的稳定性,富集在晶界处的K+因补充了晶界处正点中心的数量,使耐受8/20μs峰值电流冲击性能提高;K2O的高温液相烧结促使瓷体的气泡等烧结缺陷减少,使其2ms方波脉冲冲击性能提高;随着K掺入量的增加和烧结时间的延长,晶粒尺寸增大,压敏电压梯度减小。
洪俊伟 +3 more
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