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High Efficiency Manufacturing With a Smart Carbon Fiber End Effector 高效制造与智能碳纤维末端执行器
Pub Date : 2022-10-30 DOI: 10.1115/imece2022-94207
Carrington Chun, David A. Guerra-Zubiaga, Garrett Bailey, Kathryn Bharadwaj
Advanced industrial assembly lines often utilize large-scale robotic arms such as the Fanuc S 420-F. Such arms, and their end-effectors, are typically constructed from high-strength steel, which gives the systems superior rigidity at the cost of being very heavy. A new cutting-edge composite material, carbon fiber, offers the strength of steel at a fraction of the weight. To improve energy efficiency, this research project analyzed the feasibility of replacing the steel structure in an end-effector with a carbon-fiber composite, in addition to equipping the end effector with revolutionary ‘Smart’ technologies. Simulations performed in Siemens’ Process Simulate Tecnomatix module helped to inform mechanical energy computations for an arbitrary pick and place task and energy cost estimations were analyzed with the end-effector constructed from both steel and carbon fiber. The projected change in energy consumption for performing the pick and place task was then compared to determine the potential benefit of the carbon fiber substitution. In addition to the advanced material use, this research project also investigated the possibility of implementing ‘Smart’ technologies in the custom end effector design to further improve energy efficiency. The proposed smart technology would utilize machine vision to actively direct vacuum pressure to only the necessary suction cups in a pneumatic gripper array. Possible energy savings associated with the smart end effector design were analyzed. Simulation results for a simple pick and place operation showed that the Smart Carbon Fiber End Effector required only 2.22 Kilojoules of energy, compared to the 3.92 Kilojoules of energy needed for a Passive Steel Framed End Effector. Through creation and simulation with Digital Design Tools, the feasibility of combining advanced new structural materials with integrated intelligence was explored to create a revolutionary new end effector design that could reduce the energy consumption for a pick and place task.
先进的工业装配线经常使用大型机械臂,如发那科S 420-F。这样的臂及其末端执行器通常由高强度钢制成,这使得系统在非常沉重的代价下具有优异的刚性。一种新的尖端复合材料,碳纤维,提供了钢铁的强度和重量的一小部分。为了提高能源效率,除了为末端执行器配备革命性的“智能”技术外,该研究项目还分析了用碳纤维复合材料取代末端执行器钢结构的可行性。在西门子的Process simulation Tecnomatix模块中进行的模拟有助于为任意拾取和放置任务提供机械能计算,并分析了由钢和碳纤维构成的末端执行器的能源成本估算。然后,对执行取放任务的预计能源消耗变化进行比较,以确定碳纤维替代品的潜在效益。除了先进的材料使用,该研究项目还研究了在定制末端执行器设计中实施“智能”技术的可能性,以进一步提高能源效率。提出的智能技术将利用机器视觉主动引导真空压力到气动夹持器阵列中必要的吸盘。分析了智能末端执行器设计可能节约的能源。简单的取放操作的仿真结果表明,智能碳纤维末端执行器只需要2.22千焦耳的能量,而被动钢框架末端执行器需要3.92千焦耳的能量。通过数字设计工具的创建和仿真,探索了将先进的新型结构材料与集成智能相结合的可行性,以创建革命性的新型末端执行器设计,从而降低拾取和放置任务的能耗。
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引用次数: 0
2D Simulation of the Placement of a Pin-Through-Hole Component and Solder Paste Melting 引脚通孔元件放置和焊膏熔化的二维模拟
Pub Date : 2022-10-30 DOI: 10.1115/imece2022-95960
Nelson Rodrigues, Inês Teixeira, V. Carvalho, Duarte Santos, J. Velosa, A. Ferreira, D. Soares, J. Teixeira, S. Teixeira
In the present work, a numerical model was developed to simulate the placement of a pin through-hole (PTH) component in an aperture containing solder paste by using Ansys Fluent® software. The work uses numerical tools to understand the physical process and the solder paste behaviour for future manufacturing improvements. The component movement was simulated with the dynamic mesh model through a user-defined function (UDF). Due to software limitations, the pin of the component is already contacting the solder paste at the start of the movement. additionally, the contact detection feature was activated to prevent the pin and PCB contact during the solder paste melting. Nevertheless, the component can still move in the domain if other forces act upon it, except in the direction where the contact would occur. The second point to address is the meniscus formation process. This begins with the evaporation of the solder paste flux, causing a volume reduction followed by the melting of the metallic beads. The simulation allowed us to see that the melted solder surrounded the pin through capillarity and reproduced the phenomena of this solder printing process. This work allowed to follow the behaviour of both the component and the solder paste.
在本工作中,利用Ansys Fluent®软件开发了一个数值模型来模拟针通孔(PTH)组件在含有锡膏的孔径中的放置。这项工作使用数值工具来了解物理过程和锡膏的行为,以便将来的制造改进。采用动态网格模型,通过用户定义函数(UDF)对构件运动进行仿真。由于软件的限制,元件的引脚在运动开始时已经接触锡膏。此外,触点检测功能被激活,以防止在焊膏熔化过程中引脚和PCB接触。尽管如此,如果其他力作用在该部件上,该部件仍然可以在该域中移动,除非是在接触发生的方向上。第二点是半月板的形成过程。这始于锡膏助焊剂的蒸发,导致体积减小,随后是金属珠的熔化。通过模拟,我们可以看到熔化的焊锡通过毛细作用包围了引脚,并再现了这种焊锡印刷过程的现象。这项工作允许遵循组件和锡膏的行为。
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引用次数: 0
SMA-Based Haptic Gloves Usage in the Smart Factory Concept: XR Use Case 基于sma的触觉手套在智能工厂概念中的使用:XR用例
Pub Date : 2022-10-30 DOI: 10.1115/imece2022-94305
Rupali Srivastava, V. Kuts, Eber Lawrence Souza Gouveia, Niall Murray, D. Devine, Eoin O’Connell
Conceptualization of the Smart Factory started with introducing the Industry 4.0 paradigm and its nine pillars, which it stands. The paradigm itself is automation and robot-centric focused, which means less and less involvement of the humans on the manufacturing shop floor. However, even robots and simulation aspects of the factories are the most crucial aspects; Industry 4.0 still focuses on the Augmented and Virtual Reality (AR and VR input methods for the human operators, making the smooth transition to the Industry 5.0 concept a human-centric. Although VR/AR is still being enabled and widely used in the Human-Robot Interaction (HRI) research aspect, the heavy headset is limited in the observation field of view. The input methods, such as headsets, have voice and gesture recognition; however, those are mainly limited by factory noise and cameras pointing to the human hands. These headsets constrain the use of smart wearables to a given boundary inside the factory environment. A Shape Memory Alloy (SMA) based haptic glove with discrete data outputs from the kinaesthetic analysis of the hand bending can remove the need for gesture recognition. The paper proposes a modular framework using the SMA-based Haptic Gloves in the Smart Manufacturing environment. These gloves, without additional wearables, can enable interactions with heavy machinery, screens, and all other assets of the industrial area, even with holographic. In this paper, the authors aim to prose the context, design, and framework with the chosen use-cases mainly based on the robotic system applications in the Technological University of the Shannon: Midlands Midwest (TUS: MMW), Ireland, and Tallinn University of Technology (TalTech), Estonia.
智能工厂的概念化首先介绍了工业4.0范式及其代表的九大支柱。这种模式本身是以自动化和机器人为中心的,这意味着人类在制造车间的参与越来越少。然而,即使是机器人和工厂的模拟方面也是最关键的方面;工业4.0仍然专注于为人类操作员提供增强现实和虚拟现实(AR和VR)输入方法,使工业5.0概念以人为中心的平稳过渡。尽管VR/AR在人机交互(HRI)研究方面仍处于启用和广泛应用阶段,但笨重的头戴式设备在观察视野方面受到限制。耳机等输入法具有语音和手势识别功能;然而,这些主要受到工厂噪音和摄像头指向人手的限制。这些耳机将智能可穿戴设备的使用限制在工厂环境的给定边界内。一种基于形状记忆合金(SMA)的触觉手套,可以从手部弯曲的运动学分析中获得离散的数据输出,从而消除对手势识别的需求。本文提出了一种基于sma的触觉手套在智能制造环境中的模块化框架。这些手套不需要额外的可穿戴设备,就可以与重型机械、屏幕和工业区的所有其他设备进行交互,甚至可以使用全息技术。在本文中,作者的目标是用所选择的用例来描述上下文、设计和框架,这些用例主要基于爱尔兰香农科技大学:中部中西部(TUS: MMW)和爱沙尼亚塔林科技大学(TalTech)的机器人系统应用。
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引用次数: 1
Conveyer-Less Matrix Assembly Layout Design to Maximize Labor Productivity and Footprint Usage 无输送机矩阵装配布局设计,以最大限度地提高劳动生产率和足迹的使用
Pub Date : 2022-10-30 DOI: 10.1115/imece2022-94628
Ankur Verma, Seog-Chan Oh, James W. Wells, J. Arinez, S. Kumara
The automotive industry has used in-line conveyor systems to move vehicles through the general assembly process since the early days of vehicle manufacturing in the 20th century. With products shifting to EVs (Electric Vehicle) and the emergence of AMRs (Autonomous Mobile Robot), there is an opportunity to transform the assembly process into a more flexible conveyor-less matrix-based system. One key development need is how to structure and optimize such an asynchronous system. This paper presents a new methodology for designing a conveyor-less matrix assembly layout to maximize labor productivity, workstation utilization, and footprint usage, while minimizing the system costs, and cycle times. Specifically, we develop an asynchronous assembly system for the automotive trim area. We aim to answer the question: How do we decide on an optimum number of workstations for the asynchronous assembly system, such that productivity and ROI are maximized? For this, we use cycle times, the number of operations per workstation, reference heights, and precedence graphs as input variables. Similarity matrices are used to quantify the similarity of tools, ergonomics, and human operations between workstations. Workstation utilization percentage and makespan are the metrics used to compare between alternative layouts. Finally, we perform a cost and makespan analysis to evaluate the ratio of trim area costs to total revenue, calculate makespan, and report the best layout found in the study. Quantifying subjective data, repeatability, less setup, and simulation time are the attributes that make this methodology valuable to any virtual commissioning software, an integral part of the smart manufacturing ecosystem.
自20世纪早期的汽车制造以来,汽车工业一直使用直线输送系统来移动车辆通过总装过程。随着产品转向电动汽车(ev)和自主移动机器人(amr)的出现,有机会将装配过程转变为更灵活的基于矩阵的无输送机系统。一个关键的开发需求是如何构建和优化这样一个异步系统。本文提出了一种设计无传送带矩阵装配布局的新方法,以最大限度地提高劳动生产率、工作站利用率和占地面积利用率,同时最大限度地降低系统成本和周期时间。具体而言,我们开发了一个异步装配系统的汽车装饰领域。我们的目标是回答以下问题:我们如何决定异步装配系统的最佳工作站数量,从而使生产力和投资回报率最大化?为此,我们使用周期时间、每个工作站的操作次数、参考高度和优先级图作为输入变量。相似性矩阵用于量化工作站之间的工具、人体工程学和人类操作的相似性。工作站利用率百分比和完工时间是用来比较不同布局的指标。最后,我们进行成本和完工时间分析,以评估装饰面积成本与总收入的比例,计算完工时间,并报告研究中发现的最佳布局。量化主观数据、可重复性、更少的设置和仿真时间是使该方法对任何虚拟调试软件(智能制造生态系统的组成部分)都有价值的属性。
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引用次数: 1
Thin Steel Plate Surface Rust Recognition Using Processing Light Measurement for Reduction of Laser Cutting Defect False Recognition 利用加工光测量技术识别薄板表面锈蚀,减少激光切割缺陷的误识别
Pub Date : 2022-10-30 DOI: 10.1115/imece2022-96166
Mizuki Ishiguro, S. Warisawa, Naoyasu Narita, Hironobu Miyoshi, R. Fukui
Recently, laser cutting is an essential technology for high-speed flexible sheet-metal processing. The problem of defective cutting has occurred even with appropriate cutting parameter settings. The authors have constructed a defect recognizer that uses data of light generated during thin plate cutting, and have achieved a high recognition rate. On the other hand, some misrecognition occurred, and all of the misrecognized data were found to be workpieces with rust on the surface. Therefore, as a method to reduce misrecognition, rust information should be acquired and used for defect recognition before cutting. This study aims to acquire rust information on the workpiece surface by sensing and to recognize the existence of rust in order to reduce the false recognition in thin plate cutting defect recognition. The proposed method consists of three steps. In the first step, the surface of the workpiece is irradiated by a low-power laser, and the light generated is measured using a spectrometer installed in the laser head. In the second step, the acquired spectral data is converted into a spectrogram, and the image is binarized using Otsu’s binarization method to obtain features. In the final step, a one-class support vector machine recognizes the existence of rust on a workpiece surface from the extracted features. Verification tests using a normal and two kinds of rusted surface plates data confirmed that the proposed method accurately detected the existence of rust. (Precision = 0.89, Recall = 1.0.) It was also confirmed that the low-power laser irradiation trace did not affect the spectral data of the cutting for defect recognition.
近年来,激光切割已成为高速柔性钣金加工的一项重要技术。即使有适当的切削参数设置,也会出现切削缺陷的问题。利用薄板切割过程中产生的光数据构建了缺陷识别器,并取得了较高的识别率。另一方面,也出现了一些误认,误认数据均为表面有锈迹的工件。因此,作为一种减少误认的方法,应在切割前获取铁锈信息并用于缺陷识别。本研究旨在通过传感获取工件表面的锈蚀信息,识别锈蚀的存在,以减少薄板切割缺陷识别中的错误识别。该方法分为三个步骤。在第一步中,用低功率激光照射工件表面,并使用安装在激光头中的光谱仪测量产生的光。第二步,将采集到的光谱数据转换成光谱图,使用Otsu二值化方法对图像进行二值化,得到特征。在最后一步,一类支持向量机从提取的特征中识别工件表面是否存在生锈。采用正常和两种表面锈蚀的钢板数据进行验证试验,证实了所提出的方法能够准确检测出锈蚀的存在。(Precision = 0.89, Recall = 1.0)实验还证实了低功率激光辐照痕迹对缺陷识别的光谱数据没有影响。
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引用次数: 0
Build Chamber and Start Plate Variability During Electron Beam Melting Machine Setup 在电子束熔化机设置过程中,建立腔室和启动板的可变性
Pub Date : 2022-10-30 DOI: 10.1115/imece2022-96980
Garrett M. Kelley, Ramulu Mamidala
Electron beam melting (EBM) is an additive manufacturing process that utilizes a metallic powder as the feedstock material. During the setup of an Arcam A2X machine, the operator is first required to load the feedstock into the hoppers and set the “zero” position of the start plate relative to the rake. This manual process relies on operator-experience and is hypothesized to have a detrimental impact on process repeatability by modifying the local layer thickness. The potential effect that this has on the as-built quality and performance of EBM-manufactured components is unknown. Therefore, this study presents a device used to measure the variability that exists during A2X machine operations. Consideration is given to both the build basin as well as the start plate during ten machine setups. Assuming a mean particle diameter and commensurate layer thickness of 50 μm for Ti-6Al-4V, data indicate that local thickness deviations greater than ten layers are achievable using the prescribed zeroing routine. These deviations are shown to manifest in the measured mass of specimens within a test build. While not directly considered in this study, a discussion regarding powder pile size during fetching operations and how this may affect bed coverage and build quality is also provided.
电子束熔化(EBM)是一种以金属粉末为原料的增材制造工艺。在Arcam A2X机器的安装过程中,操作员首先需要将原料装入料斗,并设置启动板相对于耙的“零”位置。这种手工过程依赖于操作人员的经验,并且假设通过修改局部层厚度对过程的可重复性产生有害影响。这对ebm制造的组件的建成质量和性能的潜在影响是未知的。因此,本研究提出了一种用于测量A2X机器操作过程中存在的可变性的设备。在十次机器设置过程中,既要考虑构建盆,也要考虑启动板。假设Ti-6Al-4V的平均粒径和相应的层厚为50 μm,数据表明使用规定的归零程序可以实现大于10层的局部厚度偏差。这些偏差显示在测试构建中测量的样品质量中。虽然在本研究中没有直接考虑,但也提供了关于取粉操作期间粉堆大小的讨论,以及这可能如何影响床覆盖和建筑质量。
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引用次数: 0
Parametric Analysis of ANFIS, ANFIS-PSO, and ANFIS-GA Models for the Prediction of Aluminum Surface Roughness in End-Milling Operation 基于ANFIS、ANFIS- pso和ANFIS- ga模型的铝端铣表面粗糙度预测参数分析
Pub Date : 2022-10-30 DOI: 10.1115/imece2022-95418
S. Balonji, I. Okokpujie, L. Tartibu
Milling is one of the old and common cutting processes that utilize rotating tools to take materials off the main component with a combination of tools and workpiece movements. The texture of a machined surface is a key factor in defining how an essential component interacts with its environment. Trial-and-error machining to produce high-quality surfaces has been a time-consuming method that yields lower production and poor revenue. In this paper, the performances of an Adaptive Network-based Fuzzy Inference System (ANFIS) model has been employed for the prediction of the surface roughness (SR) of a block of Aluminum alloy AI6061 machined on an end-mill CNC machine by varying four input settings namely: The spindle speed of rotation, the tool cutting rate, the radial depth, and the axial depth. The approach consisted of a parametric analysis carried out within each system to obtain the finest models for the prediction. The hybrids ANFIS-PSO and ANFIS-GA have been employed to find out which one, either PSO or GA, optimizes better ANFIS for the prediction of Al6061 SR. Their performances produced better results than the stand-alone ANFIS, with ANFIS-GA yielding the best results of the most negligible RMSE value of 0.01097 and the regression values of 0.9939 for training and 0.8102 for testing.
铣削是一种古老而常见的切削工艺,它利用旋转刀具通过刀具和工件运动的组合从主要部件上取下材料。机械加工表面的纹理是定义基本组件如何与其环境相互作用的关键因素。通过试错加工来生产高质量的表面一直是一种耗时的方法,产量低,收入低。本文利用基于自适应网络的模糊推理系统(ANFIS)模型的性能,通过改变主轴转速、刀具切削速率、径向深度和轴向深度四种输入设置,对数控立铣床上加工的AI6061铝合金块的表面粗糙度(SR)进行预测。该方法包括在每个系统中进行参数分析,以获得预测的最佳模型。我们利用ANFIS-PSO和ANFIS-GA的混合模型,找出在预测Al6061 sr时,PSO和GA哪一个能更好地优化ANFIS。它们的性能优于单独的ANFIS,其中ANFIS-GA的结果最好,最可忽略的RMSE值为0.01097,训练回归值为0.9939,测试回归值为0.8102。
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引用次数: 0
Derivation of the Exact Curvature Formulation for Gothic Arch Ball Screw Grooves 哥德拱球丝杠槽精确曲率公式的推导
Pub Date : 2022-10-30 DOI: 10.1115/imece2022-95746
A. Bertolino, Andrea De Martin, Stefano Mauro, M. Sorli
No exact formulations are present in literature to calculate the principal curvatures of the ball screw grooves, while approximate equations are commonly adopted due to their simplicity. However, they derive from the ball bearing theory and do not take into account ball screw’s characteristic main geometric parameters, such as the helix angle. This leads to approximation relative errors up to 50% for commercial off-the-shelf ball screws. In this paper a new exact explicit exact solution is proposed by means of a rigorous mathematical approach. The helix angle and a generic gothic arch shape of the raceway profile are taken into account. The results of the exact and literature formulations are presented and compared. The principal curvature is seen to be strongly dependent on the helix angle and, therefore, the proposed exact solution should be used in the design phase and, in general, when high accuracy is required, such as in high-fidelity models for prognostic activities.
目前文献中没有精确的公式来计算滚珠丝杠槽的主曲率,而由于其简单性,通常采用近似方程。然而,它们来源于滚珠轴承理论,没有考虑到滚珠丝杠的特征主要几何参数,如螺旋角。这导致商用现成滚珠丝杠的近似相对误差高达50%。本文采用严格的数学方法,提出了一种新的精确显式精确解。考虑了螺旋角和滚道轮廓的一般哥特式拱门形状。给出了精确公式和文献公式的计算结果,并进行了比较。主曲率被视为强烈依赖于螺旋角,因此,建议的精确解决方案应在设计阶段使用,通常,当需要高精度时,例如在用于预测活动的高保真模型中。
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引用次数: 0
Analysis of 3D Printing Performance Using Machine Learning Techniques 利用机器学习技术分析3D打印性能
Pub Date : 2022-10-30 DOI: 10.1115/imece2022-94000
K. Kabengele, L. Tartibu, I. Olayode
Additive manufacturing (AM) or 3D printing is gaining momentum in the market compared to conventional subtractive technologies due to its ability to speedily produce complex and customized geometries with less waste of material. Some 3D printing parameters are influential or crucial as they affect the final part’s mechanical properties based on the technology used. These are the printing height, the printing rate, the nozzle diameter, the nozzle movement rate, the layer thickness, the temperature, the ventilator speed, the print precision, the layer thickness, the type of infill, and the extrusion. This paper proposes the development of a neural networks model (ANN) and a hybrid neural network trained by particle swarm optimization (ANN-PSO) to get an insight into the selection of 3D printing parameters and adjust them. To ensure the quality of the 3D printing, a parametric analysis has been performed to identify the best configuration of the models. Readily available data has been used to demonstrate the potential of the proposed approach. These data have been used to train and test the algorithms and build robust models able to predict performance. The ANN and the ANN-PSO models have exhibited good overall performance that demonstrates the potential for modelling and prediction of 3D printing performance using machine learning techniques.
与传统的减法技术相比,增材制造(AM)或3D打印在市场上的势头越来越大,因为它能够快速生产复杂的定制几何形状,同时减少材料浪费。一些3D打印参数是有影响的或至关重要的,因为它们会影响基于所使用技术的最终部件的机械性能。这些是打印高度,打印速度,喷嘴直径,喷嘴运动速度,层厚度,温度,通风机速度,打印精度,层厚度,填充类型和挤出。本文提出发展神经网络模型(ANN)和粒子群优化训练的混合神经网络(ANN- pso)来深入了解3D打印参数的选择和调整。为了保证3D打印的质量,进行了参数分析,以确定模型的最佳配置。已使用现成的数据来证明所建议的方法的潜力。这些数据已被用于训练和测试算法,并建立能够预测性能的稳健模型。ANN和ANN- pso模型表现出良好的整体性能,表明了使用机器学习技术建模和预测3D打印性能的潜力。
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引用次数: 0
Sustainable Production of Rotationally Symmetrical Components: Approaches to Resource Saving on Tool and Workpiece 旋转对称部件的可持续生产:刀具和工件资源节约的途径
Pub Date : 2022-10-30 DOI: 10.1115/imece2022-95378
P. Volke, G. Brock, S. Berger, J. Saelzer, J. Nickel, D. Biermann
Sustainability is an increasingly important trend, giving great potential in industrial production to save resources and energy. This paper presents fundamental research results on the reduction of cutting-tool consumption and saving on workpiece-material. For the basis of a new wear model, explicit knowledge of the thermo-mechanical loads and relative speeds between the tribological partners is of central importance. Therefore, a special open tribometer will be used to parameterize a friction model depending on relative speeds. Both, uncoated and coated tools are used. To reduce experimental effort, numerical simulations serve as an efficient representation of the cutting process. As a novelty in the project’s further course, both the experimentally determined tool temperatures and the friction conditions will be recorded in dependence on the tool wear, complemented by synchronized digitized wear images for validation purposes. The second work focuses on burnishing as a post-processing method for additively manufactured components. Compared to conventional machining, material and energy is saved and the workpieces’ surface integrity is improved, potentially increasing the components’ lifetime. Experimental tests are extended by finite element simulations, enabling investigations at different scales: At a workpiece model size of several millimeters, residual stresses are to be predicted; at a micrometer range, the surface smoothing is mapped.
可持续发展是一个日益重要的趋势,在工业生产中节约资源和能源具有巨大的潜力。介绍了基础研究结果减少刀具对工件材料消费和储蓄。对于一个新的磨损模型的基础,明确的知识,热机械载荷和相对速度之间的摩擦学伙伴是至关重要的。因此,将使用一个特殊的开放式摩擦计来参数化依赖于相对速度的摩擦模型。,使用裸和涂布工具。为了减少实验工作量,数值模拟可以作为切削过程的有效表示。作为该项目进一步发展过程中的一项创新,实验确定的刀具温度和摩擦条件都将根据刀具磨损情况进行记录,并辅以同步的数字化磨损图像,以进行验证。第二项工作侧重于抛光作为增材制造部件的后处理方法。相比传统的加工,材料和能源保存和工件的表面质量得到了改进,可能增加组件的生命周期。通过有限元模拟扩展了实验测试,可以在不同的尺度上进行研究:在几毫米的工件模型尺寸上,要预测残余应力;在微米范围内,表面平滑被映射。
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引用次数: 0
期刊
Volume 2B: Advanced Manufacturing
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