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Friction 2024年第3期12卷 375-395页

作者： Xiao YANG Heli LIU Lemeng ZHANG Yiran HU Denis J.POLITIS Mohammad M.GHARBI Liliang WANG Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK Department of Mechanical and Manufacturing Engineering University of CyprusNicosia 1678Cyprus Quaker Houghton deutschland gmbh Dortmund 44319Germany

The accurate representation of tribological boundary conditions at the tool–workpiece interface is crucial for analysis and optimization of formability,material flow,and surface quality of components during metal forming *** has been found that these tribological conditions vary spatially and historically with process parameters and contact *** time-dependent tribological behaviours are also known as transient tribological phenomena,which are widely observed during forming processes and many other manufacturing application ***,constant friction values are usually assigned to represent complex and dynamic interfacial conditions,which would introduce deviations in the relevant *** this paper,transient tribological phenomena and the contemporary understanding of the interaction between friction and wear are reviewed,and it has been found that these phenomena are induced by the transitions of friction mechanisms and highly dependent on complex loading conditions at the *** modelling techniques for transient behaviours for metal forming applications are also *** accurately describe the evolutionary friction values and corresponding wear during forming,the advanced interactive friction modelling has been established for different application scenarios,including lubricated condition,dry sliding condition(metal-on-metal contact),and coated system.

关键词： transient tribological phenomena interactive friction mechanism modelling techniques metal forming

Mechanism of cross-level settlements and void accumulation of wide and conventional sleepers in railway ballast

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Railway Engineering Science 2024年第3期32卷 361-383页

作者： Olga Nabochenko Mykola Sysyn Norman Krumnow Szabolcs Fischer Institute of Railway Systems and Public Transport Technical University of DresdenDresdenGermany Rhomberg Sersa deutschland gmbh BerlinGermany Central Campus Győr Széchenyi István UniversityGyorHungary

The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance ***,the mechanism of the irregularities initiation and development is *** motivation of the present study was the previous experimental studies on the application of wide sleepers in the ballasted *** long-term track geometry measurements with wide sleepers show an enormous reduction of the vertical longitudinal irregularities compared to the conventional ***,wide sleepers had higher twist and cross-section level *** present paper aims to explain the phenomenon by discrete element method(DEM)modeling the development process of sleeper inhomogeneous support at cross-level depending on the sleeper *** DEM simulations show that the maximal settlement intensity is up to 3.5 times lower for a wide sleeper in comparison with the conventional ***,the cross-level differential settlements are almost the same for both *** particle loading distribution after all loading cycles is concentrated on the smaller area,up to the half sleeper length,with fully unloaded zones under sleeper *** flow limitation under the central part of the sleeper could improve the resilience of wide sleepers to the development of cross-level *** mechanism of initiation of the cross-level irregularity is proposed,which assumes the loss of sleeper support under sleeper *** further growth of inhomogeneous settlements along the sleeper is assumed as a result of the interaction of two processes:ballast flow due to dynamic impact during void closing and on the other side high pressure due to the concentration of the pressure under the middle part of the *** DEM simulation results support the assumption of the mechanism and agree with the experimental studies.

关键词： Wide sleeper Ballasted track Sleeper support inhomogeneity Sleeper foot form Discrete element modeling Void accumulation

In memory of Friedrich Ackermann:a personal view

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Geo-Spatial Information Science 2023年第2期26卷 153-155页

作者： Ralf W.Schroth Blom deutschland gmbh SchorndorfGermany

The paper contains the author’s personal account of the professional achievements of Professor Friedrich(Fritz)Ackermann based on the author’s memories and private documents which demonstrate Ackermann’s significant influence throughout various professional phases over a period of four *** structure of the paper is based on the path of the author’s studies,the period as a member of the Institute of Photogrammetry at Stuttgart University,and finally,a professional career in photogrammetry,geoinformation and *** emphasis is on the character and skills of Friedrich ***,team spirit and social skills are demonstrated with impressive examples.

关键词： finally professional gramme

A Vital Prerequisite for Successful Copper Plating!One green acid cleaner for all kinds of HDI and MLB substrates

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A Vital Prerequisite for Successful Copper Plating!One green...

Problem Solving Solutions in Thermal Spray:HSE and Overspray

2016中国高端SMT学术会议

作者： Ramona S.Mertens Dr.Eckart Klusmann Henning Hbner atotech deutschland

by acid cleaners is a vital process step in order to grant successful copper plating within the PCB *** described pretreatment is intended for multiple use,*** MLB as well as HDI applications in hoist type *** fact offers a tremendous flexibility to PCB *** article describes a novel high performance pretreatment which cleans and activates the electroless copper layer on a biodegradable basis without harming the dry film.

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有色金属（冶炼部分） 2008年第S1期 139-145页

作者： Hans Keller Joachim Beczkowiak Stefan Zimmermann Benno Gries Jürgen Fischer H.C.Starck gmbh LaufenburgDeutschland H.C.Starck gmbh GoslarDeutschland

目前金属基材料的原材料成本对热喷涂涂层的经济性造成压力。特别是材料挥发和近期铼、钨、钴和镍基材料的价格增长,对各应用领域的许多涂层的经济性造成严重威胁。由于沉积效率的限制,喷涂中未沉积物问题变得越来越重要,不仅只是减少浪... 详细信息

目前金属基材料的原材料成本对热喷涂涂层的经济性造成压力。特别是材料挥发和近期铼、钨、钴和镍基材料的价格增长,对各应用领域的许多涂层的经济性造成严重威胁。由于沉积效率的限制,喷涂中未沉积物问题变得越来越重要,不仅只是减少浪费,还可以从材料自身价值角度去看。回收是解决这个问题的一个措施,特别是当废料中含有高价值金属时。欧洲执行的REACH(化学制品的注册、评估、授权)将会逐步强制淘汰标有有毒的材料和物质的使用。在热喷涂中使用这些有毒物质或使用热喷涂产品可能暂时是安全的,然而,从法律限制和从其他工业领域得到的指示表明,像WC-Co粉末这样的化学制品对人体有害。要想在将来的涂层工厂中保持竞争性,必须符合不断提高的更严格的环保和安全规程。

关键词：热喷涂粉末 WC-Co 健康和环保毒物学回收喷涂中未沉积物

CLEANER PRODUCTION METHODS IN ELECTROPLATING A STRATEGIC APPROACH FOR SUSTAINABLE DEVELOPMENT

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CLEANER PRODUCTION METHODS IN ELECTROPLATING A STRATEGIC APP...

Connected morphable components-based multiscale topology optimization

2004北京推动电镀与精饰清洁生产技术论坛

作者： Dr.Martin Kurpjoweit Vice President-General Metal Finishing atotech deutschland gmbh ErasmusstraBe 20 10553 Berlin GERMANY

For decades, electroplating technologies had the reputation of being highly polluting and waste ***, this has changed significantly during the last ten to fifteen years. Avoiding the use and forma-tion of hazardous substances, recycling of process chemicals, and the reduction of all kinds of waste materi-als has become one of the key development ***, several European regulations with a global application horizon like End-of-Live-Vehicle (ELV)and Waste-of-Electronic-and-Electrical-Equipment (WEEE) have increased the motivation for companiessupplying this industry to develop systems responding to these demands.

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Frontiers of Mechanical Engineering 2019年第2期14卷 129-140页

作者： Jiadong DENG Claus B.W.PEDERSEN Wei CHEN Department of Mechanical Engineering Northwestern UniversityEvanstonIL 60208USA Dassault Systemes deutschland gmbh 200095 HamburgGermany

The advances of manufacturing techniques,such as additive manufacturing,have provided unprece-dented opportunities for producing multiscale structures with intricate latticed/cellular material microstructures to meet the increasing demands for parts with customized ***,there are still difficulties for the state-of-the-art multiscale topology optimization(TO)methods to achieve manufacturable multiscale designs with cellular materials,partially due to the disconnectivity issue when tiling material *** paper attempts to address the disconnectivity issue by extending component-based TO methodology to multiscale structural *** effective linkage scheme to guarantee smooth transitions between neighboring material microstructures(unit cells)is devised and *** with the advantages of components-based TO,the number of design variables is greatly reduced in multiscale TO *** is employed to calculate the effective material properties of the porous materials and to correlate the macro/structural scale with the micro/material *** of the objective function with respect to the geometrical parameters of each component in each material microstructure have been derived using the adjoint *** examples demonstrate that multiscale structures with well-connected material microstructures or graded/layered material microstructures are realized.

关键词： multiscale topology optimization morphable component material microstructure homogenization

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用于硬金镀层电镀的高速金钴电镀工艺

用于硬金镀层电镀的高速金钴电镀工艺

2011年全国电子电镀及表面处理学术交流会

作者： Olaf Kurtz Jürgen Barthelmes Robert Rüther Michael Danker Florence Lagorce-Broc Felix Bozsa David Brookes Patrick Lam atotech deutschland gmbh atotech UK atotech Asia Pacific

＜正＞前言在电子产品的生产应用中,一般会采用电镀或浸金镀层作为导电和抗腐蚀的最终镀层。目前电子工业的金用量约占全球金总产量的8%。现今业界对功能性镀层的技术要求正在日益增加,如提高产品在日常环境中的抗腐蚀性能以及提高其导... 详细信息

＜正＞前言在电子产品的生产应用中,一般会采用电镀或浸金镀层作为导电和抗腐蚀的最终镀层。目前电子工业的金用量约占全球金总产量的8%。现今业界对功能性镀层的技术要求正在日益增加,如提高产品在日常环境中的抗腐蚀性能以及提高其导热和导电性能等,同时也要求表面保持极低的摩擦系数以降低表面磨损。

关键词：硬金镀层电镀高速金钴电镀工艺沉积速率电流密度上限

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尼龙(PA)电镀前处理

电镀与涂饰 2009年第9期28卷 14-15页

作者： Maja-Mariola Brandes Carl Christian Fels 高俊健 atotech deutschland gmbh Berlin Germany 安美特(中国)化学有限公司香港九龙

介绍了适用于尼龙(PA)基材的新型前处理工艺。经过膨胀、调校、钯活化、还原、化学镍(δ=0.3μm)、预镀镍或铜(δ=2～5μm)、酸铜(δ=20μm)、光亮镍(δ=12μm)、装饰铬(δ=0.3μm)等工艺后,可在尼龙表面获得结合力良好的装饰性镀层。... 详细信息

介绍了适用于尼龙(PA)基材的新型前处理工艺。经过膨胀、调校、钯活化、还原、化学镍(δ=0.3μm)、预镀镍或铜(δ=2～5μm)、酸铜(δ=20μm)、光亮镍(δ=12μm)、装饰铬(δ=0.3μm)等工艺后,可在尼龙表面获得结合力良好的装饰性镀层。该工艺为开发尼龙塑料在电镀业的应用迈出了重要的一步。

关键词：尼龙电镀前处理装饰性镀层

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腐蚀保护层中六价铬含量分析

电镀与涂饰 2009年第10期28卷 26-28页

作者：林子丰 Roland Vogel Claudia Andrle 安美特化学有限公司香港九龙 atotech deutschland gmbh Berlin Germany

六价铬是一种致癌物质,它在汽车和电子工业中的应用受到欧盟的严格限制。目前,在腐蚀保护层中测定Cr(VI)的分析方法已经颁布实施。本文介绍了可用于上述两个行业的Cr(VI)检测标准──EN 15205和IEC 62321,并讨论了两者的差别。

关键词：钝化膜六价铬检测标准