2015 IEEE 61st Holm Conference on Electrical Contacts (Holm)最新文献

{"title":"Three-level multi-scale modeling of electrical contacts sensitivity study and experimental validation","authors":"V. Yastrebov, G. Cailletaud, H. Proudhon, Frederick S. Mballa Mballa, S. Noel, P. Teste, F. Houzé","doi":"10.1109/HOLM.2015.7355130","DOIUrl":"https://doi.org/10.1109/HOLM.2015.7355130","url":null,"abstract":"An experimental and numerical study of electrical contact for low currents in sphere-plane set-up is presented. A three-level multi-scale model is proposed. We use the finite element analysis for macroscopic mechanical and electric simulations. It takes into account the setup geometry, elasto-plastic mechanical behavior of contacting components in the finite-strain-plasticity framework and electrostatic properties. A sensitivity analysis with respect to the brass plastic behavior and to the thickness of coating layers is also performed. The finite element results are used for an asperity-based model, which includes elasto-plastic deformation of asperities and their mutual elastic interactions. This model enables us to simulate the real morphology of contact spots at the roughness scale using the experimentally measured surface topography. Finally, the Greenwood multi-spot model is used to estimate the electrical contact resistance. This three-level model yields results which are in good agreement with experimental measurements carried out in this study.","PeriodicalId":448541,"journal":{"name":"2015 IEEE 61st Holm Conference on Electrical Contacts (Holm)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124178670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The influence of the thickness of electrodes on constriction resistance in nanofabricated sample for physical simulating of the electrical contacts","authors":"Y. Fukuyama, Norihiko Sakamoto, N. Kaneko, T. Kondo, M. Onuma","doi":"10.1109/HOLM.2015.7355079","DOIUrl":"https://doi.org/10.1109/HOLM.2015.7355079","url":null,"abstract":"Contact resistance of electrical contact in connectors consists of film resistance which is caused by high resistivity material such as oxidized metal or contamination and constriction resistance that result from narrowing current. About the latter, to establish a relationship between the physical structure of electrical contact boundary and the resistance in actual consumer connectors, we fabricate samples that represented the contact-simulated structure via nanofabrication and measure their constriction resistance. By comparing those measurement results with theoretical values, we have reported the validation of this technique. Constriction resistance is dependent on the size and/or shape of contact point. In addition to contact resistance, the thickness of the electrodes is important factor for real connectors. We measured the resistance of samples which have varying thickness of the metal layer assuming electrodes to know the influence of the thickness of electrodes on constriction resistance. Consequently, it is obtained that constriction resistance and contact area size are correlating and the constriction resistance converges in the case that the thickness of the electrodes is more than about ten times of the diameter of contact area.","PeriodicalId":448541,"journal":{"name":"2015 IEEE 61st Holm Conference on Electrical Contacts (Holm)","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129409651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of electrical contacts on a nanometer scale using a Nano-manipulator in Scanning Electron Microscope","authors":"T. Kondo, J. Toyoizumi, M. Onuma, Tetsuo Shimizu, S. Kawabata, N. Watanabe, K. Mori","doi":"10.1109/HOLM.2015.7355107","DOIUrl":"https://doi.org/10.1109/HOLM.2015.7355107","url":null,"abstract":"The indentation using tin oxide film which was deposited on tin substrate was executed by a tungsten probe whose curvature was about 5 micro meter in radius with a nano-manipulator in Scanning Electron Microscope. We measured contact resistance and the load force simultaneously, found cracks of tin oxide layer and tin penetration into the cracks and investigated in detail the correlation between indented surface morphology and electrical resistance characteristics with respect to load force by changing indentation depth. In case of 100 nm oxide film, abrupt electrical resistance decrease was observed by applying load force about 1.0×10-3N. The increase of tin penetration area on indented surface correlated with the abrupt electrical resistance decrease. This directly indicated that tin penetration into the cracks and tin appearances on the oxide surface were crucial phenomena for reliable electrical contact. Nano-manipulator used in this study was a powerful instrument for basic research of electrical contacts and realization of the miniaturized and lower load force connector.","PeriodicalId":448541,"journal":{"name":"2015 IEEE 61st Holm Conference on Electrical Contacts (Holm)","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129460266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mathematical models of heat and mass transfer in electrical contacts","authors":"S. Kharin","doi":"10.1109/HOLM.2015.7354949","DOIUrl":"https://doi.org/10.1109/HOLM.2015.7354949","url":null,"abstract":"Mathematical models describing phenomena of heat and mass transfer in electrical contacts are based on systems of partial differential equations for temperature and electromagnetic fields. The influence of Joule, Kohler and Thomson heat sources on the temperature field in closed contacts is discussed. The mathematical model of the ring-shaped welding in closed contacts is presented. Dynamics of contact opening is considered as consecutive stages including the initial stage of heating up to the melting point, the stage of a liquid bridge, metallic and gaseous arc stages. The dimensionless criteria of Thomson and Kohler are introduced which may be responsible for the displacement of the hottest isotherms of a bridge from its middle and corresponding bridge material transfer. The conditions for self-restrained bridge transfer are discussed. Phenomenon of contact floating due to metallic vapour pressure produced by a vacuum micro-arc is investigated experimentally and then described by a mathematical model. A mathematical model is presented describing transient phenomena accompanied a vacuum short arc at the initial stage of contact opening. It enables to describe the evolution of transient short anode dominated arc, which appears just after the rupture of molten bridge, into diffusive cathode dominated arc. The mechanisms of arc erosion are described by several models due to evaporation, droplets ejection, Marangoni effect, ejection of solid particles at thermo-elastic stresses. The hybrid mathematical model is elaborated to describe dynamics of the arc and forces acting in contact gap. It includes experimental oscillograms of current, voltage and contact displacement and nonlinear equations for arc, anode and cathode temperature fields and contact motion. It is shown theoretically and confirmed experimentally that in the range of high current the force of metallic vapour pressure at arcing in vacuum is comparable with magnetic repulsion force and should be taken into consideration.The mathematical model describing transition from arc to glow at contact opening in circuits with a high inductance and small current is elaborated and identified experimentally. The mechanism of thermionic emission from the cathode surface based on Richardson-Dushman equation is corrected by addition of another emission mechanism due to electrochemical phenomena in melted pool on the cathode. The influence of current frequency on the rate of the arc erosion at contact opening is investigated using the model of transition of the metallic arc phase into gaseous phase.","PeriodicalId":448541,"journal":{"name":"2015 IEEE 61st Holm Conference on Electrical Contacts (Holm)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129756432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The development of a finite element contact model of a rough surface applied to a Au-coated carbon nanotube composite","authors":"Hong Liu, J. McBride, M. Down, S. H. Pu","doi":"10.1109/HOLM.2015.7355100","DOIUrl":"https://doi.org/10.1109/HOLM.2015.7355100","url":null,"abstract":"Multi-walled carbon nanotubes (MWCNTs) coated surfaces have been developed to improve the lifetime of electrical contact of MEMS switches. However, little research has been done on the contact mechanics of the surfaces. The surfaces, usually gold coated, demonstrated a complex structure due to the gold penetrating into MWCNT and a much higher roughness than metal surfaces, with Ra in the order of 1-2 μm. This study is based on a finite element model of a bi-layered structure model for Au/MWCNT composite that includes the surface roughness. The goal is to build up a model much closer to real surfaces, and real surface data was used in the modeling. It is shown that it is only a few asperities making contact due to the roughness, and the contact area is much smaller than that of smooth surface.","PeriodicalId":448541,"journal":{"name":"2015 IEEE 61st Holm Conference on Electrical Contacts (Holm)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123267939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electron beam characterization techniques for the study of wear in sliding contacts","authors":"C. Holzapfel, C. Pauly, M. Engstler, F. Mucklich","doi":"10.1109/HOLM.2015.7355102","DOIUrl":"https://doi.org/10.1109/HOLM.2015.7355102","url":null,"abstract":"In this study different methods for studying phenomena of adhesive wear in sliding electrical contacts using electron beam characterization methods within a dual beam workstation are presented. The interface between the substrate and transferred material is complex exhibiting small grain size as well as mechanical deformation. For this purpose, a dual beam workstation is used in order to perform high resolution imaging, structural investigation by electron backscatter diffraction as well as FIB cross sectioning. Only a combination of different imaging techniques with different contrast mechanisms can provide a full understanding of the wear mechanism. During wear a prow is formed on the slider. The structure implies a multi-generation history. The deformation texture resembles a simple shear texture, which is in agreement with the presumed deformation mode. The study mainly gives a guideline for future work in the field of wear in sliding contacts.","PeriodicalId":448541,"journal":{"name":"2015 IEEE 61st Holm Conference on Electrical Contacts (Holm)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132657803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of wear volume on sliding contacts using cellular automata","authors":"K. Mashimo, H. Nishikubo, Y. Ishimaru, Y. Okuno, S. Kawata","doi":"10.1109/HOLM.2015.7355129","DOIUrl":"https://doi.org/10.1109/HOLM.2015.7355129","url":null,"abstract":"In previous research, by conducting fretting analyses and experiments on tin-plated connector terminals, the importance of rotational motion and its advantages in modeling the fretting phenomena were revealed. Rotational motion is dominant in the typical fretting driven by vibration. Additionally, linear sliding is difficult to analyze because of the asymmetry of the fretting trace. This paper presents the predictions of comparative abrasion quantities for rotational sliding. The wear volume was estimated using focused ion beam (FIB) milling and imaging. Though the actual fretting trace is not perfectly symmetric, the model can be constructed on the basis of axial symmetry for explaining average wear volume. An algorithm for the predicting comparative abrasion quantities in the rotational case was applied. It uses shear stress distribution along with the radius of the fretting traces. Cellular automaton is the main process of this analytical approach. The attributes of a cell are shear stress, wear volume, and material strength. The stress and volume (height) are updated at each increment.","PeriodicalId":448541,"journal":{"name":"2015 IEEE 61st Holm Conference on Electrical Contacts (Holm)","volume":"609 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132753971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Arcing voltage for a medium-voltage air load break switch","authors":"N. Støa-Aanensen, M. Runde, Anders Dall'Osso Teigset","doi":"10.1109/HOLM.2015.7355081","DOIUrl":"https://doi.org/10.1109/HOLM.2015.7355081","url":null,"abstract":"Air is an environmentally benign and attractive alternative to SF6 as arc quenching gas in switching devices for modest current and voltage ratings. Several interruption tests with a simple air medium-voltage load break test switch have been carried out to investigate the arc and the arcing voltage behavior for different circuit and switch design parameters. During the first half-cycle after contact separation, the arc voltage is typically 100 - 200 V. Approximately 50 μs before current zero the arc voltage increases in magnitude, before collapsing at current zero. The arc voltage increases with increasing contact gap, with decreasing current, and with increasing air flow. The arc voltage measurements from this work are believed to be suitable as experimental reference for verifying results from computational current interruption models.","PeriodicalId":448541,"journal":{"name":"2015 IEEE 61st Holm Conference on Electrical Contacts (Holm)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133118001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effectiveness of oxygen plasma versus UHV bakeout in cleaning MEMS switch surfaces","authors":"Changho Oh, F. Streller, R. Carpick, M. D. de Boer","doi":"10.1109/HOLM.2015.7355121","DOIUrl":"https://doi.org/10.1109/HOLM.2015.7355121","url":null,"abstract":"MEMS switch reliability studies have identified contamination of the electrical contact surfaces as an important source of failure. It has been previously reported that the formation of electrically insulating organic deposits degrades switch performance by increasing contact resistance. Previously, we performed a high temperature bakeout under ultra-high vacuum (UHV) to desorb possible contaminant sources from Pt electrodes prior to cycling tests in a MEMS switch. In this work, an in-situ plasma-cleaning method of Pt is assessed for its ability to actively remove adsorbed contaminants. Microswitch contact resistance is measured before and after UHV bakeout or plasma cleaning of the switches. While plasma cleaning is seen to reduce water contact angle, it raises contact resistance. The likely reason is the formation of a metal oxide on the switch surface associated with sputtering of the plasma electrode material.","PeriodicalId":448541,"journal":{"name":"2015 IEEE 61st Holm Conference on Electrical Contacts (Holm)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115556274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Composition characteristics of bronze coating systems and their influence on contact properties in electrical applications","authors":"F. Ostendorf, Michael Hermsen, A. Meyerovich","doi":"10.1109/HOLM.2015.7355093","DOIUrl":"https://doi.org/10.1109/HOLM.2015.7355093","url":null,"abstract":"Noble metal coating systems are typically used in electrical contacts to provide a reliable and robust functional capability. Due to high and volatile costs of noble metals, it is an ongoing demand to reduce noble metal consumption in contact applications by utilizing a resource-conserving process. The present study addresses the development of alternative bronze coating systems with contact characteristics similar to silver. The new bronze coating systems do not only excel by their contact characteristics, but also emerge due to their improved wear and corrosion resistance. Standard pin and socket contacts were used to determine the tribological and electrical properties of different bronze coating systems. A systematic variation of the electroplating conditions and the electrolyte composition was used to determine the influences on the layer composition as well as the mechanical and electrical properties. Contact resistance measurements, mating cycles and storage under different climatic conditions were carried out to ascertain the main coating characteristics for separable connector applications. Finally, SEM and EDX measurements were used to characterize the wear tracks as well as the corrosion performance in more detail. During all tests stable and low contact resistances are measured. Therefore bronze coating systems can enable the reduction or replacement of standard noble metal coating systems in certain applications.","PeriodicalId":448541,"journal":{"name":"2015 IEEE 61st Holm Conference on Electrical Contacts (Holm)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128397509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}