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Analysis of biobased cooling lubricants in milling stainless steel for aerospace applications – A study of tribology and performance

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Procedia CIRP 2024年 125卷 113-118页

作者： Erik Selbmann Johanna Sophie Hagen Albrecht Hänel Anas Ben Achour Uwe Teicher Christoph Herrmann Steffen Ihlenfeldt Fraunhofer Institute for Machine Tools and Forming Technology IWU 01187 Dresden Germany Fraunhofer Instiute for Surface Engineering and Thin Films IST 38108 Braunschweig Germany TU Braunschweig Institute for Machine Tools and Process Technology 38106 Braunschweig Germany TU Dresden Institute of Mechatronic Engineering 01062 Dresden Germany

Due to high thermomechanical loads, metal cutting processes generally require cooling and lubrication solutions to minimize friction between tool and workpiece. Nowadays, the standard in industry is the application of mineral-oil-based coolants, which represent a significant share of the CO 2 -footprint in production systems in terms of their extraction, fabrication and disposal. The demand for ecological innovations pushes the manufacturing sector to apply sustainable and health compatible coolant alternatives based on renewable vegetable oils for safer work environments and greener production systems. In this work, both mineral-oil-based cooling lubricants and several water-miscible emulsions based on vegetable oils were prepared and tested regarding their suitability for milling tasks of aircraft stainless steels. Therefore, comprehensive tribological investigations were carried out to determine the friction conditions in the contact zone between the tool cutting edge and the workpiece. Additionally, extensive experimental investigations were carried out to measure the process forces and the resulting tool wear as technical performance indicators of the cooling lubricants during machining. The study shows the significant potential of bio-based cooling lubricants as high-performance alternatives to conventional cooling lubricants when milling aircraft stainless steels, regarding the improvement of the tribological system of machining processes and the work environment.

关键词： Bio-based cooling lubricants tribology friction process forces tool wear

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Efficient data acquisition for traceability and analytics 31

Efficient data acquisition for traceability and analytics

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31st CIRP Conference on Life Cycle Engineering, LCE 2024

作者： Reinhardt, Heiner Mahdaviasl, Mahtab Prell, Bastian Mauersberger, Anton Klimant, Philipp Reiff-Stephan, Jörg Ihlenfeldt, Steffen Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Straße 88 Chemnitz09126 Germany Technical University of Applied Sciences Wildau Hochschulring 1 Wildau15745 Germany Virtual Technologies Hochschule Mittweida University of Applied Sciences Technikumplatz 17 Mittweida09648 Germany Institute of Machine Tools and Control Engineering Technische Universität Dresden Dresden01062 Germany

Implementing processes for traceability is required in various industries to assure product quality during manufacturing, provide evidence on required processing conditions or facilitate product recalls. Commonly, radio-frequency identification (RFID) or code recognition techniques (e.g. Data Matrix) are applied to track the flow of workpieces through a manufacturing system and link processing data accordingly. Although the analysis of tracking data is well-examined, we still see a gap in the research on the trade-off between data acquisition, data analytics and data quality. Here, we present a framework to increase the value of existing data by enabling data analytics while addressing common pitfalls and reducing the costs of data management. © 2024 Elsevier B.V.. All rights reserved.

关键词： Decision making

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Concentric jet for confined mask-less anodic dissolution and oxidation of aluminium 23

Concentric jet for confined mask-less anodic dissolution and...

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23rd International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2023

作者： Martin, André Quitzke, Susanne Morgenstern, Roy Schubert, Andreas Lampke, Thomas Chemnitz University of Technology Institute for Machine Tools and Production Processes Professorship Micromanufacturing Technology Reichenhainer Str. 70 Chemnitz09126 Germany Chemnitz University of Technology Institute of Materials Science and Engineering Materials and Surface Engineering Erfenschlager Str. 73 Chemnitz09125 Germany Fraunhofer Institute for Machine Tools and Forming Technology Reichenhainer Str. 88 Chemnitz09126 Germany

ISBN: (纸本)9781998999132

Anodic oxide layers are established for wear and corrosion protection of surfaces of aluminium parts and for decoration purposes. Usually, anodizing is carried out in large scale on the whole part surface or locally by masking through immersion in an electrolytic bath. Applying a free jet of electrolyte offers laterally confined anodizing without extensive efforts for masking and enables local functionalization without undesired influence on the surrounding surfaces in a resource- and energy-efficient process. However, the high ohmic resistance of anodic oxides leads to a wide distribution of the current density hindering laterally confined anodizing. More sharp-contoured anodic oxides are aspired through dilution of the electrolyte film flowing off laterally from the aluminium surface. For this purpose, a concentric arrangement of an electrolyte jet surrounded by a jet of deionized water was realized. Investigations on the distribution of electric current density were carried out by electrochemical machining experiments (Jet-ECM). The application of an actively anodic dissolving electrolyte of NaCl indicates the widening of the current density distribution in terms of pitting corrosion. Compared to the free electrolyte jet surrounded by atmospheric air, a wider current density distribution was detected when applying a concentric jet of deionized water. But the shape of the dissolved cavities was not widened, which indicates only low current density values on the surrounding surface. Verification experiments on anodization confirm the comparably strong localization of anodic oxides with concentric jet and an increase in thickness compared to the results with free electrolytic jet. It was found that this is mainly because of the high ohmic resistance of the anodic oxide formed on the surrounding surface and its increasing resistance at farther lateral distance from the jet due to stronger electrolyte dilution. © 2023 Euspen Headquarters.

关键词： Electrolytes

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Target Costing as an Approach to reduce Costs in closed-loop Agriculture Systems - Application for the Cultivation of Algae in Photobioreactors 30

Target Costing as an Approach to reduce Costs in closed-loop...

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30th CIRP Life Cycle Engineering Conference, LCE 2023

作者： Stange, Maximilian Tieding, Marc Brinitzer, Gordon Ihlenfeldt, Steffen Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Strasse 88 Chemnitz09126 Germany Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB Nobelstrasse 12 Stuttgart70569 Germany Institute of Mechatronic Engineering Technische Universität Dresden Dresden01069 Germany

The rapidly growing world population, the consequences of climate change and conventional agriculture as well as the limited resources of our planet threaten the food supply of humanity, especially with vital proteins. Therefore, innovation of agricultural systems is crucial for global food security and sustainable development. One proposed system is the cultivation of algae in artificially illuminated photobioreactors, which is a promising technology to limit land and water use. To achieve a competitive position between other agricultural systems and to reduce costs in a systematic and proactive approach, we suggest using Target Costing (TC) at an early stage of development. The paper aims to provide an overview of the state of the art in TC of agricultural systems. The authors identify a suitable approach for the economic evaluation of algae cultivation in bioreactors and adapt it specifically for the extraction of proteins. Based on this, different scenarios are discussed how a cost reduction of the existing systems can be achieved. The focus is on the reduction of energy costs, a suitable site selection and the use of side streams and products. © 2023 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://***/licenses/by-nc-nd/4.0)

关键词： Proteins

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Increasing Energy Efficiency in Hot forming Processes Through Multivalent Data Use 9

Increasing Energy Efficiency in Hot Forming Processes Throug...

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9th International Conference on Hot Sheet Metal forming of High-Performance Steel, CHS2 2024

作者： Polster, Stefan Boesler, Martin Straube, Oliver Lösch, Siegfried Brenne, Thomas Fraunhofer Institute for Machine Tools and Forming Technology Reichenhainer Str. 88 Chemnitz09126 Germany Gestamp Autotech Engineering Deutschland GmbH August-Thyssen-Str. 1 Ludwigsfelde14974 Germany AutoForm Engineering Deutschland GmbH Joseph-von-Fraunhofer-Straße 13a Dortmund44227 Germany

ISBN: (纸本)9780930767303

The energy policy requirements help to make industrial production more sustainable and environmentally friendly, reduce energy consumption and lower the overall costs for businesses. There is a great need for action to increase energy efficiency in production in press hardening processes through efficient technologies along entire process chains. In such production processes and process chains, data accumulates from a wide variety of sources, including machine controls, sensors, material data and simulation data from process design. The logical next step is to utilize this data along with machine learning and optimization methods to control the process and pursuing objectives like optimal quality, minimal energy, or fast cycle times. This is where the proposed method of this work comes in. The main contribution of this work is a methodology to schematically describe and handle process optimizations model-based. In addition, this method is demonstrated on a hot forming process using hybrid (simulation and experimental) data. It is shown that the process can be optimized regarding its energy consumption while complying with additional technical and quality boundary conditions. © CHS2 2024 . All rights reserved.

关键词： Energy efficiency

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Innovative actuating process for machining CFRP with force-controlled radial feed movement

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Procedia CIRP 2023年 119卷 669-674页

作者： Marie Peter Konstantin Sauer Joachim Regel Martin Dix Institute for Machine Tools and Production Processes Chemnitz University of Technology Reichenhainer Str. 70 09126 Chemnitz Germany Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Str. 88 09126 Chemnitz Germany

The use of lightweight materials such as carbon fibre reinforced plastics (CFRP) is increasing due to the demand for rising resource and energy efficiency, especially in the aerospace and automotive industries. Because of the high delamination tendency of these materials and their abrasive impact on the tool, the challenges in machining CFRP lie primarily in the drilling process and thus in the design of the drilling tool. In this paper, an innovative design of a drilling tool for machining CFRP with force-controlled radial feed movement of the cutting edges is presented. The aim of this tool is to create a tool axial force free process that uses a force-controlled radial feed motion, which matches the chip cross-section to the wear condition of the cutting edge. The tool concept is explained based on the functionality of the actuating process. Tests were evaluated with regard to process forces and drilling quality to show that the tool is capable of producing delamination-free bores in a tool axial force free process.

关键词： tool design adaptive control actuator drilling composite

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Investigation of Surface Characteristics in Magnetic Field assisted Electrical Discharge Machining

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Procedia CIRP 2024年 123卷 416-421页

作者： Viet D. Bui André Martin Thomas Berger Andreas Schubert Chemnitz University of Technology Professorship Micromanufacturing Technology Reichenhainer Str. 70 09126 Chemnitz Germany Fraunhofer Institute for Machine Tools and Forming Technology Reichenhainer Str. 88 09126 Chemnitz Germany

Electrical discharge machining (EDM) has demonstrated its promising potential for surface modification. The integration of materials from tool electrode or powder that is mixed into the dielectric fluid has proven to modify the workpiece surface to enhance its mechanical properties, realize antibacterial effects, or increase biocompatibility. Recent EDM studies showed that due to non-contact forces, properties of the modified surface such as roughness values and the thickness of modified layer were significantly influenced when using magnetic field assisted EDM. Consequently, in this study, an external magnetic field with a strength of 0.66 T is used to assist the material transfer from tool electrode to workpiece surfaces during the EDM process. Pure silver and copper tools with a diameter of 2 mm are used to modify surfaces of Ti6Al4V workpieces at a discharge energy of 125 µJ with different polarities. Results show that the assistance by magnetic field significantly increases the content of transferred material from tool electrode to the workpiece surface. Additionally, it increases material removal rate and reduces the modified layer thickness. Magnetic field assisted EDM is a potential technology for improving the efficacy of the EDM surface modification.

关键词： EDM magnetic field deposition modified surface

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Shaping of Sharp-Edged Design Elements by Electromagnetic forming 13th

Shaping of Sharp-Edged Design Elements by Electromagnetic Fo...

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13th International Conference on the technology of Plasticity, ICTP 2021

作者： Psyk, Verena Scheffler, Christian Stalmann, Albrecht Goede, Martin Fraunhofer Institute for Machine Tools and Forming Technology Chemnitz Germany Volkswagen AG Wolfsburg Germany

ISBN: (纸本)9783030753801

Modern car body design includes parts with sharp-edged elements, which are challenging for conventional sheet metal forming technologies. This is especially critical when implementing aluminum parts in order to consider lightweight design requirements. Applying high strain rates allows increasing formability for numerous materials, including typical aluminum alloys used in the automotive industry. Therefore, integrating high-speed forming into a conventional process can help to extend forming limits. The feasibility of locally sharpening a deep-drawn radius by integrated electromagnetic forming was proved in the literature, but up to now, the investigated target radii were much larger compared to the sheet thickness. The presented paper shows that target radii in and below the size of the sheet thickness are possible by this process combination. Based on a simplified 2D component geometry, complementary experimental and numerical investigations served for developing different variants of a modular test tool and analyzing the influence of important process and tool parameters on the forming result. © 2021, The Minerals, Metals & Materials Society.

关键词： Automotive industry

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Investigations on Case Hardening of an Additive Manufactured Steel 20MnCr5 (via PBF-LB/M)

Investigations on Case Hardening of an Additive Manufactured...

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作者： Mallow, S. Schmitt, M. Gebauer, M. Stockburger, R. Reich, M. Kessler, O. Materials Science University of Rostock Albert-Einstein-Straße 2 Rostock18059 Germany Fraunhofer Institute for Casting Composite and Processing Technology Igcv Augsburg Germany Fraunhofer Institute for Machine Tools and Forming Technology Iwu Dresden Germany Hanomag Härtol Lohnhärterei GmbH Gommern Germany

As an additive manufacturing process, powder bed fusion of metals using a laser beam (PBF-LB/M) enables the near-net-shape production of complex components in a single step. In combination with case hardening, it will thus be possible in the future to produce lightweight, functionally integrated transmission components characterized by high-strength surface layers with a sufficiently tough component core. However, the process-related new initial conditions resulting from very high solidification rates in PBF-LB/M may mean that case hardening of PBF-LB/M materials with standard parameters achieves different case hardening results than have been usual in the past. This hypothesis was investigated in the present work using the case hardening steel 20MnCr5 (material number 1.7147) after successful development of industry-relevant PBF-LB/M parameters. Besides the convincing results regarding microstructure, hardness and carbon depth profiles, case hardening with standard parameters led to irregular grain growth due to holding at high temperatures for several hours during carburization. © 2023 Walter de Gruyter GmbH, Berlin/Boston, Germany.

关键词： 3D printing

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Planar 3D-Printing and Intrinsic Heat Generation Thermoforming of a Fully Customizable Ankle Orthosis – A Feasibility Approach

Planar 3D-Printing and Intrinsic Heat Generation Thermoformi...

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Integrated Systems in Medical Technologies (ISMT)

作者： Johannes Knecht Marcel Müller Franziska Valerie Hagenauer Linda Weisheit Valentin Wilhelm Mauersberger Lukas Boxberger Biomechatronics Fraunhofer Institute for Machine Tools and Forming Technology IWU Dresden Germany Technical Design Technical University of Dresden Dresden Germany

ISBN: (数字)9798350375527

ISBN: (纸本)9798350375534

There is a wide spectrum of injuries and medical conditions that are treated with the use of orthoses. For better comfort fully customized orthoses are designed and manufactured via 3D-printing or thermoforming thermoplastic casts with a low glass transition and softening temperature nowadays. This study aims to print a planar orthosis design and then thermoform the orthotic blank with intrinsic heating to get the final customized design depending on patient's needs. After identifying possible thermoplastic polymers for the application with differential scanning calorimetry (DSC) to determine thermal properties, tensile testing for mechanical properties and peel-off testing to measure multi material printing adhesion, the final orthosis blank is printed using Wire-EncapsulatingAdditiveManufacturing to integrate heating wires into the structure and create the intrinsic ability of heat generation for the thermoforming process.

关键词： Heating systems Printing Temperature Wires Thermoforming Mechanical factors Softening Plastics Wearable devices Testing

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