辐射交联对高分子聚合物PTCR热敏电阻器电性能的影响

辐射交联对用于过流保护的高分子聚合物ＰＴＣＲ热敏电阻器之电性能有较大的影响。实验证明：辐照强度有一个最佳范围,正确选择辐照强度可提高高分子聚合物ＰＴＣＲ热敏电阻器的升阻比,改善动作特性及耐压、耐电流等电性能。     

C-2CH复合型PTCR薄膜

采用溶胶包裹再凝胶工艺制备了Ｃ－２ＣＨ复合型ＰＴＣＲ薄膜。实验表明，这种材料的ＰＴＣ效应是由２ＣＨ的相变体膨胀引起的，Ｃ的粒径大小对复合薄膜ＰＴＣ特性有十分显著的影响。较高的热循环温度和较多的热循环老化次数使ＰＴＣＲ薄膜电性能重现性得以改善。     

PTC热敏陶瓷电极的老化研究

研究了ＰＴＣ热敏陶瓷四种电极的热老化。通过实验比较表明，烧渗铝电极较适用于ＰＴＣ热敏陶瓷。     

塑料材料在土壤中腐蚀（老化）行为研究

对埋藏在全国土壤腐蚀试验网站中的PE、PVC、PA材料性能进行了分析测试、比较。结果表明，在各种不同的土壤中三种材料均较好地保持了各自的机械物理性能及电性能等特性，在长期埋地环境中自然老化速度较慢，耐土壤腐蚀性能良好，将三种材料进行比较，其中PE材料的防蚀性能最好。     

液相添加剂对PTCR陶瓷电性能的影响

液相添加剂ＡＳＴ（Ａｌ２Ｏ３＋ＳｉＯ２＋ＴｉＯ２）对ＢａＴｉＯ３陶瓷材料电性能的影响很大，随着Ａｌ２Ｏ３含量的增加，材料的电性能降低；ＳｉＯ２、ＴｉＯ２的物理特性对材料电性能影响较大；过量ＴｉＯ２对材料ＰＴＣ效应有重要影响，适当过量ＴｉＯ２含量，可得到性能优良的ＰＴＣＲ陶瓷。     

天然硫化橡胶热氧老化中太赫兹介电谱

天然橡胶制品的老化是其使用中普遍存在的现象,老化的本质是材料本身存在缺陷而容易被外部因素影响。介电谱是表征电介质对电磁波频率或温度的依赖关系,是微观极化的一种宏观体现。参照橡胶热空气老化标准GB/T3512-2014,对天然硫化橡胶在100℃实验箱中进行了1 000余小时热氧实验,研究样品的太赫兹介电谱随老化时间的变化关系。通过跟踪测试,获取了橡胶每24 h在0.2~1.2 THz的复介电常数和损耗角正切值有效数据,根据复介电常数数值可以推导橡胶的极化特点和统计性的微观运动类型,进而分析用太赫兹介电谱表征的天然硫化胶热氧老化过程中分子结构变化和相互的对应关系。由于材料老化的相通性,该结果对研究其他高分子材料的老化也能起到积极的意义。     

高分子材料老化分析与防老化措施分析

高分子材料具有非常优异的新能,用途非常广泛,具有很高的市场占有率。但由于高分子材料在广泛使用过程中受到光照、湿度以及温度等外界多种环境因素影响与作用,导致其力学性能和外观结构发生变化,容易老化。为进一步提高高分子材料的抗老化性能,必须充分认识影响其老化的各种因素,分析其老化机理及老化进程。本文分析了引起高分子材料老化的因素,详细分析各种老化措施,建立了较为完善的老化与防老化的综合评价体系。     

大功率PTC发热体的设计及老化特性研究

主要研究了ＰＴＣ材料的开关温度、样品的室温电阻及耗散系数等特性参数对发热体功率的影响。从实用的角度阐述了合理设计发热体各种电热参数的重要性。在对ＰＴＣ发热体进行的老化试验的基础上，探讨了提高ＰＴＣ大功率发热体可靠性的因素。     

TiO_2粒子尺寸及其分布对BaTiO_3系PTC热敏电阻电性能的影响

研究了ＴｉＯ２粒子尺寸及其分布对ＢａＴｉＯ３系ＰＴＣ热敏电阻元件一些电性能的影响，并探讨了有关机理。研究表明，粒子平均尺寸增大，可使室温电阻率ρ２５和耐电压Ｖｂ适当提高，但可能使ＰＴＣ效应有所下降；粒子尺寸分布变宽可使ρ２５和Ｖｂ下降，但可能使ＰＴＣ效应增强。     

导电聚合物延长了电路的寿命

如果你的设计需要一个体积小，并且无需维修的装置来代替保险丝保护电路，你可以选用由导电聚合物制成的正温度系数热敏电阻—ＰＴＣ电阻。正如其名，当电流过大时，ＰＴＣ电阻值迅速并大幅度地增加，从而达到了保护电路的目的。当ＰＴＣ电阻值增加时，ＰＴＣ电阻将电路中的电流控制在足够低的水平，使被保护的电路免遭损坏。（见图１）当故障被排除或电源被切断后，ＰＴＣ电阻值又恢复到能使电路正常工作的阻值。与普通保险丝不同，ＰＴＣ电阻持久耐用，不需要维修和更换（见图２）。聚合物保护：导电聚合物ＰＴＣ电阻是一种小到可以用于表…     

BaTiO_3系PTCR热敏电阻器用烧结助剂的研究

研究了烧结助剂的作用，实验结果表明：如只引入半导化元素，不引入烧结助剂，则室温电阻率ρ２５很大，甚至是绝缘体。由于烧结助剂的加入，既改善了ＰＴＣＲ热敏电阻陶瓷的烧结性，又改善了其ρ２５、耐电压Ｖｂ、ＰＴＣ效应等特性，从而使产品的各种特性易于重复。烧结助剂昔日多用ＡＳＴ，现在常用ＳｉＯ２，其加入量ｘ宜小于２％。ＳｉＯ２的纯度、杂质等化学特性，与粒子形状、粒度分布、晶系等物理特性，对ＰＴＣＲ热敏电阻器的电性能有很大的影响。据此提出了ＢａＴｉＯ３系ＰＴＣＲ热敏电阻器用ＳｉＯ２的技术标准。     

电解电容器快速老练工艺的研究

分析传统老练工艺的缺点, 指出老练的目的是恢复电解电容器固有的电性能。研究老练温度、老练时间对产品电性能的影响。提出了快速老练新工艺, 老练时间只有３ ｈ。采用优质的电解液是快速老练的前提     

Si_3N_4在BaTiO_3基低阻高性能PTCR陶瓷材料中的作用

要同时保证 PTCR材料和元件具有低室温电阻率和较高的 PTC特性 ,有较大难度。研究了添加 Si3N4作为烧结助剂 ,对 PTCR材料的显微结构和电学性能的影响。同添加 Si O2 作为烧结助剂相比 ,添加 1.0 %的 Si3N4的 PTCR材料更易同时满足低阻高性能要求。     

电极对PTC热敏电阻老化性能的影响

为探究电极因素对PTC热敏电阻老化性能的影响,分别对烧渗Al电极,烧渗Ag-Zn电极和烧渗Ni电极等三种类型的PTC热敏电阻元件进行了老化试验。结果显示:烧渗Ag-Zn电极的元件有较好的老化性能,阻值变化率?R/R≈–4%,电流冲击失效率≈0。从材料热力学和电极的电化学两方面,对该老化特性进行了分析,表明材料热膨胀失配和电极电化学不稳定性,是电极影响元件老化性能的两大因素。     

The contact resistance and reliability of anisotropicallyconductive film (ACF)

The effect of bonding pressure on the electrical and mechanical properties of anisotropic conductive film (ACF) joint using nickel particles and metal-coated polymer ball-filled ACFs was investigated. The contact resistance decreases as the bonding pressure increases. Contact resistance of ACF is determined by the contact area change between particles and contact substrates. Electrical conduction through the pressure engaged contact area between conductive particles and conductor substrates is the main conduction mechanism in ACF interconnection. In addition, environmental effects on contact resistance and adhesion strength such as thermal aging, high temperature/humidity aging and temperature cycling were also investigated. Interestingly, the contact resistances of the excessively bonded samples deteriorated more than those of optimally bonded ones. Increasing contact resistance and decreasing adhesion strength after harsh environmental tests were mainly due to the loss of contact by thermal stress effect and moisture absorption, and also partially due to the formation of metal oxide on the conductive particles     

The coupling effects of temperature,electric current and stress on the adhesion and electrical properties of COG assembly

This paper reports the adhesion and electrical properties of chip-on-glass (COG) assembly undergoing the coupling loads of temperature, electric current and stress (hygrothermal stress or thermal stress). Firstly, the effects of loading rate and coupling loads on the adhesive force of COG assembly were studied by shear test. The maximum shear force of COG assembly firstly increases and then decreases with increasing loading rate in range of 10–70 μm/s, peaks at the loading rate of 50 μm/s. When the COG assembly was exposed in the coupling loads of temperature, electric current and hygrothermal stress, its maximum shear force decreases with the increase of hygrothermal aging time. However, as for thermal cycling aging time increases, the maximum shear force increases initially and then decreases for the COG assembly under the coupling loads of temperature, electric current and thermal stress. The functions of the maximum shear force with aging time were obtained by fitting experiment data. Secondly, the real-time resistances of COG assembly during shear test and aging process were detected using two-point probe. In shear process, the real-time resistance increases insignificantly in elastic deformation stage but increases rapidly in viscoelastic deformation stage prior to the fracture. Due to the combined influences of temperature, electric current and stress, the resistance increases remarkably with the increase of hygrothermal aging time and it increases slightly with the increase of thermal cycling aging time. However, the real-time resistance exhibits circulation changes corresponding to thermal cycling. Finally, the relationship of resistance with the maximum shear force of energized COG assembly versus environmental aging times was studied.     

锂掺杂NiMn系NTC热敏电阻的制备与性能研究

介绍对ＮｉｘＭｎ３－ｘＯ４ＮＴＣ热敏电阻材料进行锂掺杂的两种方法，并对掺杂后的电阻性能进行了研究。结果表明：掺杂后仍可获得尖晶石结构的半导瓷，但阳离子分布改变；在晶粒间界处发生偏析；掺Ｌｉ后电阻率、材料常数Ｂ基本不变，但电学稳定性提高。     

Thermally Stable Silver Nanowire–Polyimide Transparent Electrode Based on Atomic Layer Deposition of Zinc Oxide on Silver Nanowires

The performance of a flexible transparent conductive electrode with extremely smooth topography capable of withstanding thermal processing at 300 °C for at least 6 h with little change in sheet resistance and optical clarity is reported. In depth investigation is performed on atomic layer deposition (ALD) deposited ZnO on Ag nanowires (NWs) with regard to thermal and atmospheric corrosion stability. The ZnO coated nanowire networks are embedded within the surface of a polyimide matrix, and the <2 nm roughness freestanding ­electrode is used to fabricate a white polymer light emitting diode (PLED). PLEDs obtained using the ZnO‐AgNW‐polyimide substrate exhibit comparable performance to indium tin oxide (ITO)/glass based devices, verifying its efficacy for use in optoelectronic devices requiring high processing temperatures.