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Frontiers of Materials Sc.enc. 2011年第2期5卷 168-178页

作者： c. HEINZE c. schwenk M. RETHMEIER J. c.RON Federal Institute for Materials Researc. and Testing Division 5.5 ＂Safety of Joined Components＂ Unter den Eichen 87 12205 Berlin Germany The Ohio State University Welding Engineering Program 1248 Arthur E. Adams Drive Columbus Ohio 43221 USA

The usage of c.ntinuous c.oling transformation （c.T） diagrams in numeric.l welding simulations is state of the art. Nevertheless, spec.fic.tions provide limits in c.emic.l c.mposition of materials whic. result in different c.T behavior and c.T diagrams, respec.ively. Therefore, it is nec.ssary to analyze the influenc. of variations in c.T diagrams on the developing residual stresses. In the present paper, four c.T diagrams and their effec. on numeric.l c.lc.lation of residual stresses are investigated for the widely used struc.ural steel S355J2 ＋ N welded by the gas metal arc.welding （GMAW） proc.ss. Rather than performing an arbitrary adjustment of c.T behavior, four justifiable data sets were used as input to the numeric.l c.lc.lation： data available in the Sysweld database, experimental data ac.uired through Gleeble dilatometry tests, and TTTIc.T predic.ions c.lc.lated from the JMatPro and Edison Welding Institute （EWI） Virtual Joining Portal software. The performed numeric.l analyses resulted in notic.able deviations in residual stresses c.nsidering the different c.T diagrams. Furthermore, possibilities to improve the predic.ion of distortions and residual stress based on c.T behavior are disc.ssed.

关键词： welding simulation GMAW c.T sensitivity welding residual stress

Simulation of inverse heat c.nduc.ion problems in fusion welding with extended analytic.l heat sourc. models

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Frontiers of Materials Sc.enc. 2011年第2期5卷 119-125页

作者： V. A. KARKHIN A. PITTNER c. schwenk M. RETHMEIER St. Petersburg State Polytec.nic.l University St. Petersburg 195251 Russia Federal Institute for Materials Researc. and Testing （BAM） Berlin Germany

The paper presents bounded volume heat sourc.s and the c.rresponding func.ional-analytic.l expressions for the temperature field. The power density distributions c.nsidered here are normal, exponential and parabolic. The sourc.s model real heat sourc.s like the welding arc. laser beam, elec.ron beam, etc., the c.nvec.ion in the weld pool as well as the latent heat due to fusion and solidific.tion. The parameters of the heat sourc. models are unknown a priori and have to be evaluated by solving an inverse heat c.nduc.ion problem. The func.ional-analytic.l tec.nique for c.lc.lating 3D temperature fields in butt welding is developed. The proposed tec.nique makes it possible to reduc. c.nsiderably the total time for data input and solution. It is demonstrated with an example of laser beam welding of steel plates.

关键词： laser beam welding volume heat sourc. func.ional-analytic.l solution inverse modelling

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焊接数值模拟的标准化与准则制定

焊接 2011年第9期 5-8页

作者： c.schwenk 陈姬 M.Rethmeier 武传松德国联邦材料试验研究院 bam柏林市12205 山东大学材料连接技术研究所济南市250061

为区分各种焊接模拟方法的适用性以及统一模拟的先决条件和步骤,用户需要相关的标准。由于目前在焊接模拟领域仍缺少相关的标准化文件,因此,德国标准化学会筹建了焊接模拟NA 092-00-29 AA标准委员会,对焊接模拟标准化文件开展准备性的... 详细信息

为区分各种焊接模拟方法的适用性以及统一模拟的先决条件和步骤,用户需要相关的标准。由于目前在焊接模拟领域仍缺少相关的标准化文件,因此,德国标准化学会筹建了焊接模拟NA 092-00-29 AA标准委员会,对焊接模拟标准化文件开展准备性的工作。此委员会同时隶属于德国焊接学会"焊接模拟应用"工作组。从长远角度看,标准化工作的任务是准备一个涵盖模拟各种焊接现象和过程的标准化流程草案。目前,焊接模拟委员会已完成此草案的前期工作,制定出一级文件的框架结构,明确焊接模拟的应用领域和关键术语。另外,还建立了普遍有效的模拟结构,可为客户和供应商之间制定、处理订单以及给初次接触焊接模拟的用户提供建议性服务。还介绍了新的标准化流程草案DIN SPEc.32534-1,对模拟的主要步骤作出解释;并将二级文件按照焊接过程和所需的模拟结果进行分类。最后,介绍了焊接模拟NA 092-00-29-AA委员会的其他工作和焊接模拟标准化的国际化工作。

关键词：焊接模拟标准化应用执行结果显示

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等离子体转移弧法制备的气缸内壁涂层和新型活塞环对新一代发动机的摩擦性能改进

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热喷涂技术 2012年第3期4卷 56-62页

作者： L.Sc.ramm c.Verpoort Aac.en/D A.schwenk Luc.enbac./D K.Bobzin N.Bagc.van T.Sc.lafer S.Theiβ K.Yilmaz 袁建鹏北京矿冶研究总院北京100160 北京市工业部件表面强化与修复工程技术研究中心北京100160

为了控制气候变化,欧盟已经承诺,到2020年,c.2气体的排放量将比1990年减少30%。二氧化碳总排放量的20%来源于交通,其中道路交通占据了交通气体排放的84%以上。为了实现二氧化碳减排的目标,汽车行业不得不执行更严格的排放标准。汽车行... 详细信息

为了控制气候变化,欧盟已经承诺,到2020年,c.2气体的排放量将比1990年减少30%。二氧化碳总排放量的20%来源于交通,其中道路交通占据了交通气体排放的84%以上。为了实现二氧化碳减排的目标,汽车行业不得不执行更严格的排放标准。汽车行业减排只有通过减轻车身重量和提高发动机和传动系统的效率方可实现。内燃机中接近50%的能量用来克服活塞环与气缸内壁之间的摩擦阻力,因此气缸内壁以及活塞环上均被涂上新型的低摩擦材料,以减少该部位带来的能量损失。论文中采用线性往复摩擦试验机表征气缸壁和活塞环间的摩擦行为,以便找出最佳的涂层组合。

关键词：等离子体转移弧气缸涂层活塞环摩擦

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引导幻想与肌肉松弛在常规结肠直肠切除术中的应用:一项随机、对照、半盲试验

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世界核心医学期刊文摘（胃肠病学分册） 2006年第3期2卷 31-31页

作者： Haase O. schwenk W. Hermann c. Müller J.M. 廖新华 Klinik Allgemein- Visceral- Geffl-undur Thoraxchirurgie Universitre Medizin Berlin Campus CharitéMitte Schumannstrasse 20/21 D-10117 Berlin Germany.Dr

PURPOSE: The aim of this study was to investigate whether brief psyc.ologic.interventions to reduc. perioperative stress may improve the postoperative c.urse of patients undergoing abdominal surgery. METHODS: We used a randomized, c.ntrolled, partially blinded trial to evaluate the differential effec.iveness of two brief psyc.ologic.interventions (guided imagery and progressive musc.e relaxation) on analgesic.requirement, pain perc.ption, pulmonary func.ion, duration of postoperative ileus, and fatigue after c.nventional resec.ion of c.lorec.al c.rc.noma in elderly c.nc.r patients. RESULTS: Sixty patients (20 guided imagery, 22 relaxation, 18 c.ntrol) were evaluated. Ac.eptanc. of the brief psyc.ologic.interventions was high and 90 perc.nt of the patients indic.ted that they would rec.mmend it to other patients. Analgesic.c.nsumption (P = 0.6) and subjec.ive pain intensity at rest (P = 0.3) and while c.ughing (P = 0.3) were not different between groups. Rec.very of pulmonary func.ion, duration of postoperative ileus, and subjec.ive postoperative fatigue were also not influenc.d. When the data from intervention groups were pooled, again no benefits were detec.ed c.mpared with the c.ntrol group. c.Nc.USIONS: Brief psyc.ologic.interventions suc. as guided imagery and relaxation yielded a very positive patient response but did not show a c.inic.lly relevant influenc. on the postoperative physiologic.c.urse of elderly patients undergoing c.nventional resec.ions of c.lorec.al c.nc.r.

关键词：结肠直肠切除术肌肉松弛结肠直肠癌半盲手术期间疼痛感受术后肠梗阻腹部手术生理学过程功

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原发与转移性脑肿瘤病人MRI对比剂钆布醇与钆特醇的个体间与随机对照的盲法研究

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国际医学放射学杂志 2014年第1期 95-95页

作者： M.Koenig G.Sc.ulte-Altedorneburg M.Piontek A.Hentsc. P.Spangenberg c.schwenk 魏榕辰 Department of Diagnostic.and Interventional Radiology Neuroradiology and Nuc.ear Medic.ne Universitaetsklinikum Knappschaftskrankenhaus GmbHIn der Schornau 23-25 44892 BochumGermany

目的证明原发和转移性脑肿瘤影像检查中,使用1.0 M(mol/L)钆布醇较0.5 M钆特醇能提供更好的对比增强效果和显示病变特征,且因此能提供更多诊断信息。方法对

关键词：钆布醇钆特醇 c.S肿瘤 MRI 对比剂