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QUALITY AND TESTING IN RESISTANCE WELDING

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QUALITY AND TESTING IN RESISTANCE WELDING

新能源电动汽车异种材料连接技术的挑战、趋势和进展

第四届海内外青年设计与制造科学会议

作者： S.Jack Hu jacek senkara Dept. of Mechanical Engineering and Applied Mechanics The University of Michigan Ann Arbor MI 48109 Welding Department Warsaw University of Technology Poland

＜正＞Because of a lack of scientific understanding of resistance spot weld quality,there is a tendency to overuse welds to fulfil design requirements of welded structures in the sheet metal welding ***,such practice faces serious challenges as more advanced materials are introduced and manufacturing processes get leaner and more *** this paper,quality and quality testing in resistance spot welding are *** quality related issues,such as materials,welding procedure and quality testing are *** quality is discussed based on a survey of various industries and professional *** process related issues,such as expulsion and defect formation,are discussed based on their influence on weld *** influence of quality testing procedures,which is often overlooked,is discussed in *** on the current status of weld quality research,it is found that a unified,scientifically developed,and universally accepted weld quality definition is the basis of controlling weld quality to meet design requirements of spot welds.

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材料导报 2019年第23期33卷 3853-3861,3881页

作者：李红刘旭升张宜生 jacek senkara 李光瀛马鸣图北京工业大学材料科学与工程学院北京100124 华中科技大学材料科学与工程学院武汉430074 华沙工业大学焊接工程系波兰华沙02-524 钢铁研究总院北京100081 中国汽车工程研究院重庆401122

多材料混合结构在车身上的应用可以实现汽车安全性、轻量化水平的共同提升,也是如今新能源汽车工业发展的一个主要方向。先进高强钢(Advanced high strength steel,AHSS)、铝合金、工程塑料以及碳纤维增强复合材料(Carbon fiber reinfor... 详细信息

多材料混合结构在车身上的应用可以实现汽车安全性、轻量化水平的共同提升,也是如今新能源汽车工业发展的一个主要方向。先进高强钢(Advanced high strength steel,AHSS)、铝合金、工程塑料以及碳纤维增强复合材料(Carbon fiber reinforced polymer,CFRP)等作为轻质高强材料的代表已广泛应用于白车身、覆盖件以及复杂结构件的制造中。

关键词：电动汽车先进高强钢铝合金碳纤维复合材料电池包异种材料连接

高熵合金在钎焊和表面工程领域的应用研究进展

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材料工程 2021年第8期49卷 1-10页

作者：李红韩祎曹健 MARIUSZ Bober jacek senkara 北京工业大学材料与制造学部北京100124 哈尔滨工业大学先进焊接与连接国家重点实验室哈尔滨150001 华沙理工大学制造工程学院波兰华沙02-524

随着合金制造水平的提高及性能要求的复杂化,高熵合金逐渐引起极大的关注。目前在材料加工领域内的研究主要集中于钎焊和表面工程两大方向。在钎焊领域,高熵合金可以作为钎焊填充材料应用于高温和低温钎焊,本文归纳了合金高熵化的相关... 详细信息

随着合金制造水平的提高及性能要求的复杂化,高熵合金逐渐引起极大的关注。目前在材料加工领域内的研究主要集中于钎焊和表面工程两大方向。在钎焊领域,高熵合金可以作为钎焊填充材料应用于高温和低温钎焊,本文归纳了合金高熵化的相关经验参数,阐述了第一性原理计算和相图计算等模拟计算手段在高熵合金填充材料设计领域内的应用;详细介绍了高熵合金钎料在镍基高温合金、陶瓷-金属异种材料、低温封装等连接领域的最新研究进展。同时,分析了工艺参数对高熵合金钎料钎焊接头组织与性能的影响。在表面工程领域,论述了高熵合金薄膜/涂层的应用方向与制备手段,总结了在高温防护涂层、硬质保护层以及其他应用领域的研究进展。同时归纳了高熵合金在钎焊和表面工程领域研究和应用中存在的问题,而未来将在降低钎料熔点、提高焊缝高温力学性能以及发展共晶高熵合金钎料/涂层等领域进一步提高研究水平。

关键词：高熵合金钎焊填充金属涂层薄膜

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先进航空材料焊接过程热裂纹研究进展

材料工程 2022年第2期50卷 50-61页

作者：李红闫维嘉张禹杜文博栗卓新 MARIUSZ Bober senkara jacek 北京工业大学材料与制造学部轻合金材料与加工研究所北京100124 华沙理工大学华沙02524

高焊接热裂纹敏感性是制约新一代合金材料在航空航天领域推广应用的技术瓶颈。本文分别从焊接热裂纹的产生机理和各类合金裂纹敏感性实验的角度梳理该方向的研究进展。焊接热裂纹主要包括凝固裂纹(在焊缝内部产生)和液化裂纹(在焊缝与... 详细信息

高焊接热裂纹敏感性是制约新一代合金材料在航空航天领域推广应用的技术瓶颈。本文分别从焊接热裂纹的产生机理和各类合金裂纹敏感性实验的角度梳理该方向的研究进展。焊接热裂纹主要包括凝固裂纹(在焊缝内部产生)和液化裂纹(在焊缝与部分熔化区交界处产生)。影响焊接热裂纹产生的因素包括材料成分、焊接热循环以及接头热应力。在梳理焊接热裂纹机理研究的基础上,分别总结了铝合金、镁合金、先进高强钢以及镍基合金焊接热裂纹的实验研究进展。建立考虑复杂多组元以及结晶形态对裂纹敏感性影响的量化判据,是该领域未来的重要发展方向。针对母材和焊材进行成分优化、添加形核剂或实施辅助工艺措施,是工程应用领域抑制热裂纹缺陷的有效方法。开展焊接热裂纹产生机理及其抑制方法研究,有助于突破新一代合金材料加工技术瓶颈,推进其在航空航天领域的应用。

关键词：热裂纹铝合金镁合金高强钢镍基高温合金

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真空钎焊不锈钢EGR冷却器用高温钎料研究进展

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电焊机 2018年第12期48卷 6-12页

作者：李红李云月栗卓新 jacek senkara 庄鸿寿陆青松北京工业大学材料科学与工程学院北京100124 华沙理工大学焊接工程系波兰华沙999038 北京航空航天大学机械工程及自动化学院北京100191 浙江银轮机械股份有限公司浙江天台317200

冷却废气再循环(EGR)系统可以有效降低汽车尾气中NOx的排放,核心部件EGR冷却器一般采用真空钎焊工艺制造。综述了应用于真空钎焊不锈钢EGR冷却器的高温钎料的研究进展,分析镍基、铜基钎料以及新型铁基钎料的优缺点,重点介绍新型铁基钎... 详细信息

冷却废气再循环(EGR)系统可以有效降低汽车尾气中NOx的排放,核心部件EGR冷却器一般采用真空钎焊工艺制造。综述了应用于真空钎焊不锈钢EGR冷却器的高温钎料的研究进展,分析镍基、铜基钎料以及新型铁基钎料的优缺点,重点介绍新型铁基钎料的研究进展。分析钎料合金元素对钎料熔融温度、钎缝组织及钎焊接头力学性能的影响,阐述钎焊工艺对不锈钢母材溶蚀和钎缝组织的影响规律,并对不锈钢高温钎料的未来研究方向和发展趋势进行了展望。

关键词：冷却器高温钎料熔融温度接头强度耐腐蚀性能

Ballistic performance of titanium-based layered composites made using blended elemental powder metallurgy and hot isostatic pressing

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DEFENCE TECHNOLOGY 2024年第9期39卷 1-14页

作者： Markovsky, Pavlo Janiszewski, jacek Savvakin, Dmytro Stasyuk, Oleksandr Fikus, Bartosz Samarov, Victor Ellison, Vianey Prikhodko, Sergey, V NAS Ukraine GV Kurdyumov Inst Met Phys 36Academician Vernadsky Blvd UA-03142 Kyiv Ukraine Jaroslaw Dabrowski Mil Univ Technol 2Gen Sylwester Kaliski Str PL-00908 Warsaw 46 Poland Synertech Inc 11711 Monarch St Garden Grove Los Angeles CA 92841 USA Univ Calif Los Angeles Dept Mat Sci & Engn Los Angeles CA 90095 USA

Metal matrix composites tiles based on Ti-6Al-4V (Ti64) alloy, reinforced with 10, 20, and 40 (vol%) of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy (BEPM) and then bonded together into 3-layer laminated plates using hot isostatic pressing (HIP). The laminates were ballistically tested and demonstrated superior performance. The microstructure and properties of the laminates were analyzed to determine the effect of the BEPM and HIP processing on the ballistic properties of the layered plates. The effect of porosity in sintered composites on further diffusion bonding of the plates during HIP is analyzed to understand the bonding features at the interfaces between different adjacent layers in the laminate. Exceptional ballistic performance of fabricated structures was explained by a significant reduction in the residual porosity of the BEPM products by their additional processing using HIP, which provides an unprecedented increase in the hardness of the layered composites. It is argued that the combination of the used two technologies, BEPM and HIP is principally complimentary for the materials in question with the abilities to solve the essential problems of each used individually.

关键词： Metal matrix composites Powder metallurgy Titanium hydride powder Master alloy Titanium carbide Titanium boride Hot isostatic pressing Ballistic tests TI-6AL-4V ALLOY TIB COMPOSITES ARMOR STEELS BEHAVIOR MICROSTRUCTURE PROJECTILES AEROSPACE

Modeling the effect of stand and site characteristics on the probability of mistletoe infestation in Scots pine stands using remote sensing data

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Forest Ecosystems 2024年第3期11卷 296-306页

作者： Luiza Tymińska-Czabańska Piotr Janiec Pawel Hawrylo jacek Slopek Anna Zielonka Pawel Netzel Daniel Janczyk Jaroslaw Socha Department of Forest Resources Management Faculty of ForestryUniversity of Agriculture in KrakowAl.29 Listopada 46Krakow31-425Poland Forest Management and Geodesy Bureau Ul.Lesnikow 2105-090Sekocin StaryPoland Department of Geoinformatics and Cartography Institute of Geography and Regional DevelopmentFaculty of Earth Sciences and Environmental ManagementUniversity of WroclawPl.Uniwersytecki 1WroclawPoland Institute of Geography and Spatial Management Faculty of Geography&GeologyJagiellonian University in KrakowUl.Gronostajowa 730-387Poland Torun Regional Directorate of State Forests Ul.Adama Mickiewicza 987-100TorunPoland

Over the past decade,the presence of mistletoe(Viscum album ***)in Scots pine stands has increased in many European *** the factors that influence the occurrence of mistletoe in stands is key to making appropriate forest management decisions to limit damage and prevent the spread of mistletoe in the ***,the main objective of this study was to determine the probability of mistletoe occurrence in Scots pine stands in relation to stand-related endogenous factors such as age,top height,and stand density,as well as topographic and edaphic *** used unmanned aerial vehicle(UAV)imagery from 2,247 stands to detect mistletoe in Scots pine stands,while majority stand and site characteristics were calculated from airborne laser scanning(ALS)*** on stand age and site type from the State Forest database were also *** found that mistletoe infestation in Scots pine stands is influenced by stand and site *** documented that the densest,tallest,and oldest stands were more susceptible to mistletoe *** type and specific microsite conditions associated with topography were also important factors driving mistletoe *** addition,climatic water balance was a significant factor in increasing the probability of mistletoe occurrence,which is important in the context of predicted temperature increases associated with climate *** results are important for better understanding patterns of mistletoe infestation and ecosystem functioning under climate *** an era of climate change and technological development,the use of remote sensing methods to determine the risk of mistletoe infestation can be a very useful tool for managing forest ecosystems to maintain forest sustainability and prevent forest disturbance.

关键词： Generalized additive models Tree infestation Mistletoe occurrence ALS UAV Scots pine

Ballistic performance of titanium-based layered composites made using blended elemental powder metallurgy and hot isostatic pressing

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Defence Technology 2024年第09期 1-14页

作者： Pavlo Markovsky jacek Janiszewski Dmytro Savvakin Oleksandr Stasyuk Bartosz Fikus Victor Samarov Vianey Ellison Sergey V.Prikhodko G.V.Kurdyumov Institute for Metal Physics of N.A.S.of Ukraine Jaros?aw Da browski Military University of Technology Synertech Inc. Department of Materials Science and Engineering University of California Los Angeles

Metal matrix composites tiles based on Ti-6Al-4V(Ti64) alloy, reinforced with 10, 20, and 40(vol%) of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy(BEPM) and then bonded together into 3-layer laminated plates using hot isostatic pressing(HIP). The laminates were ballistically tested and demonstrated superior performance. The microstructure and properties of the laminates were analyzed to determine the effect of the BEPM and HIP processing on the ballistic properties of the layered plates. The effect of porosity in sintered composites on further diffusion bonding of the plates during HIP is analyzed to understand the bonding features at the interfaces between different adjacent layers in the laminate. Exceptional ballistic performance of fabricated structures was explained by a significant reduction in the residual porosity of the BEPM products by their additional processing using HIP, which provides an unprecedented increase in the hardness of the layered composites. It is argued that the combination of the used two technologies, BEPM and HIP is principally complimentary for the materials in question with the abilities to solve the essential problems of each used individually.

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Rethinking neurodegenerative diseases:neurometabolic concept linking lipid oxidation to diseases in the central nervous system

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Neural Regeneration Research 2024年第7期19卷 1437-1445页

作者： Steinunn Sara Helgudóttir Anne Skøttrup Mørkholt jacek Lichota Preben Bruun-Nyzell Mads Christian Andersen Nanna Marie Juhl Kristensen Amanda Krøger Johansen Mikela Reinholdt Zinn Hulda Maria Jensdóttir John Dirk Vestergaard Nieland 2N Pharma ApS NOVI Science ParkAalborgDenmark Molecular Pharmacology Group Department of Health Science and TechnologyAalborg UniversityAalborgDenmark

Currently,there is a lack of effective medicines capable of halting or reve rsing the progression of neurodegenerative disorde rs,including amyotrophic lateral sclerosis,Parkinson s disease,multiple sclerosis,or Alzheimer s *** the unmet medical need,it is necessary to reevaluate the existing para digms of how to to rget these *** considering neurodegenerative diseases from a systemic neurometabolic perspective,it becomes possible to explain the shared pathological *** innovative approach presented in this paper draws upon exte nsive research conducted by the authors and researchers *** this review,we highlight the importance of metabolic mitochondrial dysfunction in the context of neurodegenerative *** provide an overview of the risk factors associated with developing neurodegenerative disorders,including genetic,epigenetic,and environmental fa ***,we examine pathological mechanisms implicated in these diseases such as oxidative stress,accumulation of misfolded proteins,inflammation,demyelination,death of neurons,insulin resistance,dysbiosis,and neurotransmitter ***,we outline a proposal for the restoration of mitochondrial metabolism,a crucial aspect that may hold the key to facilitating curative therapeutic interventions for neurodegenerative disorders in forthcoming advancements.

关键词： brain disease carnitine palmitoyl transferase 1 epigenetics metabolism gut microbiome mitochondrial dysfunction neurodegeneration oxidative stress