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Frontiers of Mechanical Engineering 2023年第4期18卷 183-193页

作者： Alexander SCHMIDT Felix JENSCH Sebastian HÄRTEL chair of hybrid manufacturing Brandenburg University of TechnologyCottbus 03046Germany

Many processes may be used for manufacturing functionally graded *** them,additive manufacturing seems to be predestined due to near-net shape manufacturing of complex geometries combined with the possibility of applying different materials in one *** adjusting the powder composition of the starting material layer by layer,a macroscopic and step-like gradient can be *** further improve the step-like gradient,an enhancement of the in-situ mixing degree,which is limited according to the state of the art,is *** this paper,a novel technique for an enhancement of the in-situ material mixing degree in the melt pool by applying laser remelting(LR)is *** effect of layer-wise LR on the formation of the interface was investigated using pure copper and low-alloy steel in a laser powder bed fusion *** cross-sectional selective electron microscopic analyses were carried *** applying LR,the mixing degree was enhanced,and the reaction zone thickness between the materials was ***,an additional copper and iron-based phase was formed in the interface,resulting in a smoother gradient of the chemical composition than the case without *** Marangoni convection flow and thermal diffusion are the driving forces for the observed effect.

关键词： multi-material additive manufacturing(MMAM) functionally graded materials(FGMs) laser powder bed fusion(L-PBF) laser remelting(LR) pure copper

Traceable long range scanning tunneling microscopy

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Optoelectronics Letters 2008年第1期4卷 49-50页

作者： A. Weckenmann J. Hoffmann chair Quality Management and manufacturing Metrology University of Erlangen-Nuremberg

Dimensionally correct and directly traceable measurement is not feasible with conventional scanning tunneling microscopy (STMs) due to severe hysteresis and non-linearity of the commonly applied piezo tube scanners and the very short range. By integrating a custom made probing system based on tunneling current measurement into a commercially available and laser-interferometrically position controlled positioning system, an STM with a principal measuring

关键词：远程扫描隧道显微镜显微镜技术干涉测量激光定位控制

Turning of aluminum metal matrix composites： influence of the reinforcement and the cutting condition on the surface layer of the workpiece

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Advances in manufacturing 2016年第3期4卷 225-236页

作者： Jan C. Aurich Marco Zimmermann Stefan Schindler Paul Steinmann Institute for manufacturing Technology and ProductionSystems University of Kaiserslautern KaiserslauternGermany chair of Applied Mechanics University of Erlangen-Nuremberg Erlangen Germany

Aluminum metal matrix composites （Al-MMCs） are difficult to machine. The reinforcement of aluminum using ceramic particles accelerates tool wear. Moreover, demanded machining accuracies or properties of the surface layer are difficult to achieve. In the present study, the effect of silicon carbide reinforcement particles on the surface layer of the workpiece was investigated using multiple cutting conditions for dry turning. Three differently reinforced Al-MMCs regarding the volume percent-age （17% and 30%） and the particle size （0.6 μm and 3 μm） and their non-reinforced matrix were considered as the workpiece materials. The reinforcement and the cutting condition affect the results of turning. A greater particle volume percent improves the surface roughness and decreases the tensile stress in the surface. The smaller particle size caused a lower tensile stress in the surface. A general effect of the particle size on the workpiece roughness can not be concluded. The most important cutting parameter for the surface layer of the workpiece is the feed. Greater feeds decrease the tensile stress in the surface, but deteriorate the surface quality.

关键词： Aluminum metal matrix composite(Al-MMC) Forces . Workpiece roughness Surface Residual stress

INTRODUCTION TO THE SPECIAL ISSUE ON MATHEMATICS AND ALGORITHMS IN COMPUTER-AIDED manufacturing,ENGINEERING,AND NUMERICAL CONTROL

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Journal of Systems Science & Complexity 2013年第5期26卷 665-666页

作者： LI Hongbo SHPITALNI Moshe Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems ScienceChinese Academy of Sciences Schlesinger chair of manufacturing Systems Technion Israel Institute of Technology

Sixty years have passed since numerical control of machine tools was first demonstrated at *** then,rapid developments in advanced manufacturing technology have posed new challenges and requirements,among them faster machining(high-speed machining),higher feed-rates,more accurate parts and better surface *** only are sophisticated computerenabling technologies needed to cope with these challenges,but also significantly improved

关键词：计算机辅助制造计算机辅助工程数学工具算法数控计算机应用技术计算机数字控制麻省理工学院

Atomic Force Microscope with an Adjustable Probe Direction and Integrated Sensing and Actuation

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Nanomanufacturing and Metrology 2022年第2期5卷 139-148页

作者： Janik Schaude Tino Hausotte chair of manufacturing Metrology Friedrich-Alexander-Universität Erlangen-NürnbergNägelsbachstr.2591052ErlangenGermany

This article presents the application and evaluation of a cantilever with integrated sensing and actuation as part of an atomic force microscope(AFM)with an adjustable probe direction,which is integrated into a nano measuring machine(NMM-1).The AFM,which is operated in closed-loop intermittent contact mode,is based on two rotational axes that enable the adjustment of the probe direction to cover a complete *** axes greatly enlarge the metrology frame of the measuring system by materials with a comparatively high coefficient of thermal expansion,which ultimately limits the achievable measurement uncertainty of the measuring ***,to reduce the thermal sensitivity of the system,the redesign of the rotational kinematics is ***,in this article,some preliminary investigations on the application of a self-sensing cantilever with an integrated micro heater for its stimulation will be *** previous investigations,a piezoelectric actuator has been applied to stimulate the ***,the removal of the piezoelectric actuator,which is enabled by the application of a cantilever with an integrated micro heater,promises an essential simplification of the sensor ***,in the future it might be possible to use materials with a low coefficient of thermal expansion,which are often difficult to machine and therefore only allow for rather simple ***,because of the creepage of piezoelectric actuators,their removal from the metrology frame might lead to improved metrological *** will be shown,there are no significant differences between the two modes of ***,the redesigned rotational system will be based on the cantilever with integrated sensing and actuation.

关键词： Atomic force microscopy Tilting AFM Piezoresistive cantilever Self-actuated cantilever Nano measuring machine

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用高氮钢制造复杂高强度零件(英文)

中国有色金属学会会刊：英文版 2012年第S2期22卷 512-518页

作者： Hannes NONEDER Marion MERKLEIN chair of manufacturing Technology Egerlandstra.e 13 91058 Erlangen Germany

High performance components, e.g., fasteners, nowadays are usually made out of cold forged and heat treated steels like steel 1.5525 (20MnB4). To overcome the problems of heat treatment, e.g., low surface quality, new workpiece materials for cold forging should be found to achieve the needlessness of heat treatment after cold forging. One possible material is given by high nitrogen steels like steel 1.3815 (X8CrMnN19-19). Due to the high strain hardening of these materials the process and tool design for an industrial batch process are challenging and should be conducted by FE-simulation. The numerical results show that, high strength tool materials, like PM-steels or cemented carbides, in most cases, are inevitable. Additionally to the selection of suitable tool materials, the tool layout should be developed further to achieve a high loadability of the tools. The FE-models, used for process and tool design, are validated with respect to the materials' flow and occurring forming force to assure a proper design process. Also the comparison of strength of components made out of steel 1.5525 in quenched and tempered conditions and steel 1.3815 in strain hardened condition is done. The results show that the component made of steel 1.3815 has a significantly higher strength than the component made of steel 1.5525. This shows that by the use of high nitrogen steels a high performance component can be manufactured by cold forging.

关键词： high nitrogen steel heat treatable steel cold forging FE-simulation Martens hardness

基于有限元和光滑粒子流体动力学的硬质工具钢切屑形貌预测方法研究（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第11期17卷 873-885页

作者： Usama UMER Jaber Abu QUDEIRI Mohammad ASHFAQ Abdulrahman AL-AHMARI Princess Fatima Alnijiris' s Research chair for Advanced manufacturing Technology (FARCAMT) Advanced Manufacturing InstituteKing Saud University Industrial Engineering Department College of EngineeringKing Saud University

目的:获得有效的高精度切屑形貌仿真方法。创新点:通过比较不同切削参数下采用光滑粒子流体动力学模型和有限元模型仿真获得的切屑形貌,证明光滑粒子流体动力学模型可以很好地实现对节状切屑的仿真,而不需要额外的几何或基于网格的切屑... 详细信息

目的:获得有效的高精度切屑形貌仿真方法。创新点:通过比较不同切削参数下采用光滑粒子流体动力学模型和有限元模型仿真获得的切屑形貌,证明光滑粒子流体动力学模型可以很好地实现对节状切屑的仿真,而不需要额外的几何或基于网格的切屑分离准则。方法:基于有限元和光滑粒子流体动力学的切削形貌仿真方法。结论:通过比较不同切削参数下采用光滑粒子流体动力学模型和有限元模型仿真获得的切屑形貌,证明了基于裂纹形成与扩展理论,采用合理疲劳参数的标准Johnson-Cook模型完全可以实现对节状切屑形成过程的仿真,也即无需采用修正的Johnson-Cook模型。同时证明了有限元模型和光滑粒子流体动力学方法均可满足不同切削速度和进给量条件下的切削力和切屑形貌仿真。

关键词：切屑形貌有限元光滑粒子流体动力学淬硬工具钢锯齿形切屑

Automated Disassembly Sequence Prediction for Industry 4.0 Using Enhanced Genetic Algorithm

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Computers, Materials & Continua 2021年第11期69卷 2531-2548页

作者： Anil Kumar Gulivindala M.V.A.Raju Bahubalendruni R.Chandrasekar Ejaz Ahmed Mustufa Haider Abidi Abdulrahman Al-Ahmari Department of Mechanical Engineering Industrial Robotics and Manufacturing Automation LaboratoryNational Institute of TechnologyKariakal609609India Department of Computer Science Engineering National Institute of TechnologyKariakal609609India Raytheon chair for Systems Engineering Advanced Manufacturing InstituteKing Saud UniversityRiyadh11421Saudi Arabia Industrial Engineering Department College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

The evolution of Industry 4.0 made it essential to adopt the Internet of Things(IoT)and Cloud Computing(CC)technologies to perform activities in the new age of *** technologies enable collecting,storing,and retrieving essential information from the manufacturing *** collected at sites are shared with others where execution automatedly *** obtained information must be validated at manufacturing to avoid undesirable data losses during the de-manufacturing ***,information sharing from the assembly level at the manufacturing stage to disassembly at the product end-of-life state is a major *** current research validates the information optimally to offer a minimum set of activities to complete the disassembly *** optimal disassembly sequence plan(DSP)can possess valid information to organize the necessary actions in ***,finding an optimal DSP is complex because of its combinatorial *** genetic algorithm(GA)is a widely preferred artificial intelligence(AI)algorithm to obtain a near-optimal solution for the DSP *** converging nature at local optima is a limitation in the traditional *** study improvised the GA workability by integrating with the proposed priori crossover *** optimality function is defined to reduce disassembly effort by considering directional changes as *** enhanced GA method is tested on a real-time product to evaluate the *** obtained results reveal that diversity control depends on the operators employed in the disassembly *** proposed method’s solution can be stored in the cloud and shared through IoT devices for effective resource allocation and disassembly for maximum recovery of the *** effectiveness of the proposed enhanced GA method is determined by making a comparative assessment with traditional GA and other AI methods at different population sizes.

关键词： Automation internet of things disassembly sequence planning priori cross over operator enhanced GA disassembly predicates

Development of Texture Mapping Approaches for Additively Manufacturable Surfaces

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 125-138页

作者： Bhupesh Verma Omid Zarei Song Zhang Johannes Henrich Schleifenbaum chair for Digital Additive Production RWTH Aachen University52074 AachenGermany

manufacturing(AM)technologies have been recognized for their capability to build complex components and hence have ofered more freedom to designers for a long *** ability to directly use a computer-aided design(CAD)model has allowed for fabricating and realizing complicated components,monolithic design,reducing the number of components in an assembly,decreasing time to market,and adding performance or comfort-enhancing *** of the features that can be introduced for boosting a component functionality using AM is the inclusion of surface texture on a given *** inclusion is usually a difcult task as creating a CAD model resolving fne details of a given texture is difcult even using commercial software *** paper develops a methodology to include texture directly on the CAD model of a target surface using a patch-based sampling texture synthesis algorithm,which can be manufactured using *** for the texture generation algorithm can be either a physical sample or an image with heightmap *** heightmap information from a physical sample can be obtained by 3D scanning the sample and using the information from the acquired point *** obtaining the required inputs,the patches are sampled for texture generation according to non-parametric estimation of the local conditional Markov random feld(MRF)density function,which helps avoid mismatched features across the patch *** generating the texture,a design constraint to ensure AM producibility is considered,which is essential when manufacturing a component using,e.g.,Fused Deposition Melting(FDM)or Laser Powder Bed Fusion(LPBF).The generated texture is then mapped onto the surface using the developed distance and angle preserving mapping *** implemented algorithms can be used to map the generated texture onto a mathematically defned *** paper maps the textures onto fat,curved,and sinusoidal surfaces for *** the texture m

关键词： Texture synthesis Design for additive manufacturing Image processing Textured surface generation Texture mapping

Analysis of defects in clean fabrication process of friction stir welding

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Transactions of Nonferrous Metals Society of China 2017年第7期27卷 1507-1516页

作者： Noor Zaman KHAN Zahid A.KHAN Arshad Noor SIDDIQUEE Abdulrahman M.AL-AHMARI Mustufa H.ABIDI Department of Mechanical Engineering Jamia Millia Islamia (A Central University) New Delhi PIN-110025 India Princess Fatima Alnijris Research chair for Advanced manufacturing Technology Advanced Manufacturing Institute King Saud University Riyadh-11421 Saudi Arabia

Striving for cleaner production is a sought-after manufacturing *** stir welding(FSW)is a joiningtechnique with par excellence and far less invasive to the environment than even best conventional welding *** is energyefficient and free from consumables,affluent and *** is,thus,accepted as a clean welding process that can produceacceptable quality *** suffers from some major challenges of defects of its own kind that subject the process open toimprovements so as to prove itself a reliable production *** study presents a holistic characterization of defects commonlyfound in FSW *** finding of the present study reveals that most defects are caused by inadequate heat generation,impropermaterial movement around the pin and inadequate material consolidation behind the *** amount of heat generation andmaterial stirring depends on several FSW parameters which may lead to the defect formation,if not selected *** resultsreported in this work are derived from sound literature support and *** are made in the form ofcharacteristics of defects such as likelihood of their location,main responsible parameters along with the recommendations forminimizing them.

关键词： clean welding process friction stir welding defect process parameter