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Failure characteristics of Ag-SnO2 contact material in AC levelMENG Fanbina,b,LU Jianguoa,ZHU Yongqinga,b,LU Ningyib,CHEN Zhichaob,and HUANG Qiutaob a Electrical Apparatus Institute,Hebei University of Technology,Tianjin 300130,China b Hongfa Electroacoustic Co.Ltd.,Xiamen 361021,China摘 要:The failure characteristics of the contact material Ag-SnO2 were......
of train and velocity distribution around contact wire in this study. The results show that the lift coefficient, lateral force coefficient and moment coefficients increase with the increase of yaw angle... than that of the 2.5 m windbreak wall. The dimensionless velocity of the contact wire at height of 5.0 m from the top of rail (TOR) significantly reduces when the wind break wall with height of 2.5 m......
Contact mode thermal sensors for ultrahigh-temperature region of 2000-3500 KSheng-Yong Xu,Zhen-Hai Wang,Li-Jiang GuiKey Laboratory for the Physics and Chemistry of Nanodevices,Department... reviewed several existing techniques that were capable of detecting local temperatures in the range of 2000-3500 K in a contact manner.These techniques included several non-standard thermocouples,Seger......
, MENSAH-BROWN H, YAYA A, et al. Calculation of interfacial tensions between macromolecular solutions and Soltrol-130 from contact angles measurements[J]. Journal of Engineering & Applied Sciences... molecular mass thermoplastic resin system CBT500/DBTL, a new method based on the harmonic mean method corrected contact angle method was proposed to study the resin mixing mechanism and to guide......
象.如果接触点发生故障,则可能影响到整个系统的可靠运行.由此引出了电接触的稳定性,寿命等与可靠性相关的研究内容[10-11].而接触电阻是电连接的一个基本,主要的参数.电接触的材料,结构,制造工艺,工作环境都有密切关系[9]. 图1 电接触的定义 Fig. 1 Definition of electrical contact 电接触的定义如图1所示:理论上接触的两个导体,由于接触表面存在初始粗糙度,实际接触的区域是如图1放大图所示的微小触点,这些实际接触的区域称为"接触斑点"(Contact spot,a-spot)[12].电流通过这些所谓的接触斑点时必然发生收缩,这样就引起了接触电阻的变化[13]. 1 实验 镍[14]和铜[15]都是常用的电接触材料,目前对上述两种材料研究较多,但是针对温度变化(室温~300 ℃)对其接触电阻影响的研究较少,为了......
接触应力峰值 Table 2 Hip joint surface contact stress of different CE angles 2.3 髋关节表面接触应力峰值综合分析结果 表3所示为通过有限元分析得到的不同CE角的髋关节生物力学模型在不同载荷方向下的髋关节表面最大接触应力. 图8所示为不同CE角的髋关节股骨头表面接触应力峰值随载荷方向的变化.其中通过有限元分...编号:1672-7207(2015)06-2081-09 Mathematics modeling and verification of hip joint surface contact stress WANG Monan, AN Xianjun (Robotics Institute, Harbin University of Science and Technology, Harbin......
for microelectronic cooling [17-19]. HUANG et al [17] reported a procedure of making wettability gradients on copper, with water contact angles gradually changing from 88° to 18°, by synthesis of cone-like... wettability surface on copper substrate 2.2 Characterization The water contact angles on copper substrate were measured by a contact angle system, OCA15 (Data Physics Instruments Company, Germany......
Arc erosion behavior of a nanocomposite W-Cu electrical contact materialCHEN Wenge,KANG Zhanying, SHEN Hongfang, and DING Bingjun School of Materials Science and Engineering, Xi’an University... microscopy. It is concluded that the nanocomposite W-Cu electrical contact material shows a characteristic of spreading arcs. The arc breakdown of a commercially used W-Cu alloy was limited in a few areas......
Contact surface fatigue life for roller rack pinion systemKIM Chang-hyun1, CHOI Heung-soap2, KWON Soon-man1(1.Department of Mechanical Design and Manufacturing Engineering, Changwon National... the variation of the shape design parameters to predict the gear surface fatigue limit which is strongly related to the gear noise and vibration at the contact patch. The results show that the pitting life can......
washed with distilled water and vacuum dried at 50 ℃ for 10 min. A water drop of about 3.5 μL was placed on the sample surface, and the readings of contact angles were taken automatically on the left... out on the surfaces immersed in distilled water. The contact angle measurement results are given in Table 2. Table 2 Water contact angles of three calcite surfaces and two fluorite surfaces immersed......