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Materials Science and technology Conference and Exhibition 2016, MS and T 2016

作者： Toeppel, Thomas Schumann, Philipp Ebert, Marie-Christin Bokkes, Tobias Funke, Kerstin Werner, Michael Zeulner, Fabian Bechmann, Florian Herzog, Frank Fraunhofer Institute for Machine Tools and Forming Technology IWU Noethnitzer Str. 44 Dresden01187 Germany Concept Laser GmbH An der Zeil 8 Lichtenfels96215 Germany

ISBN: (纸本)9781510833142

In the course of increasing application of laser beam melting (LBM) technology for series production, LBM process monitoring becomes more and more important for quality control during and after the production process. Especially for safety-relevant parts, such as aircraft and motorsport components or medical implants, process robustness and quality assurance is basic assumption for a wide adoption of LBM technology in these industries. Furthermore, real-time monitoring is fundamental for self-regulating process control of LBM machines. But before that, extensive research on interrelations between sensor signals and process conditions need to be done. In this contribution, newest results on process failure and defect detection using Concept Laser's coaxial IR camera and photodiode based QM Meltpool 3D are addressed. This systems newest 3D feature, providing a detailed 3D landscape of position-related meltpool characteristics, is compared to CT inspection data. Hence, advantages for part inspection and it's usage in research are presented. Copyright © 2016 MS&T16®.

关键词： Process monitoring

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Investigation of Turning Elastomers Assisted with Cryogenic Cooling

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Procedia CIRP 2016年 40卷 631-636页

作者： M. Putz M. Dix M. Neubert G. Schmidt R. Wertheim Technische Universität Chemnitz Institute for Machine Tools and Production Processes (IWP) Germany Fraunhofer Institute for Machine Tools and Forming Technology IWU Germany

Elastomer components are normally produced by a molding process. When it comes to small batch sizes this becomes inefficient due to the expensive production of the molding tool, and machining is an economic alternative. However, due to the very low Young's modulus elastomers are difficult to machine. The investigated approach to enhance machinability was to use cryogenic cooling during cutting elastomer components, changing their mechanical properties. Experiments in turning show that elastomers do not respond like ordinary metal materials. Hence this study is conducted to describe the effects occurring during turning elastomers assisted with cryogenic cooling. Therefore extensive tests were carried out to determine the material characteristics. Forces and tool temperatures were measured in turning tests. A rise in tangential cutting force by approximately 30% compared to dry machining verifies the change in material properties at very low temperatures. This correlates with the measured tensile strength at different temperatures. The examined surface integrity and the formed chips confirm the improvement in machinability under cryogenic conditions as a result of lower material deformation. In addition the friction between tool and chip was evaluated by applying a temperature dependent friction law.

关键词： Cutting Cryogenic machining hard-to-cut materials

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Manufacturing of Long Products Made of Innovative Lightweight Materials

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Acta Metallurgica Sinica(English Letters) 2015年第12期28卷 1496-1502页

作者： Karsten Richter Roland Müller Andreas Kunke Verena Kr? usel Dirk Landgrebe Fraunhofer Institute for Machine Tools and Forming Technology (IWU) Professorship Forming and Joining (UFF) Technische Universit?t Chemnitz

The processing of innovative lightweight materials to sheet metal components and assemblies with globally or locally defined properties is the object of this work. It takes a load-dependent design of components and assemblies, for example, based on the composition of different construction materials or a targeted setting of component areas with specified characteristics to fully exploit the lightweight potential when substituting conventionally used materials. Different process chains for the manufacturing of roll-formed long products made of magnesium alloys and high-strength steels with locally defined properties will be presented in this paper. Depending on the kind of material to be formed and the desired product characteristics, different temperature managements are needed for capable processes. Due to limited formability at room temperature, magnesium alloys require a heating of the forming zones above 200–225 °C throughout the bending process in order to activate additional gliding planes and to avoid any failures in the radii. The realization of local hardening effects requires at least one process-integrated heat treatment when roll forming manganese–boron steels. For both processes, it is imperative to realize a heating and cooling down or quenching appropriate for the manufacturing of long products with the required quality. Additionally, proper line speeds that allow a continuously operated economical production have to be considered. Research results including design, FEA, realization and experimentation of the mentioned process chains and strategies will be described in detail.

关键词： Roll forming Heat treatment Lightweight component Light metals Manganese steels AZ31 magnesium alloy

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Adaptronic Applications in Cutting machines

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Procedia CIRP 2016年 46卷 303-306页

作者： W.-G. Drossel A. Bucht K. Pagel T. Mäder T. Junker Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Str. 88 09126 Chemnitz Germany

Adaptronic systems are able to improve high performance cutting technologies making them more stable, economic and efficient leading to a higher product quality. The main objectives of adaptronic systems in production technologies, beyond controlling process parameters, are either reducing vibration or generating them. The latter topic is a highly innovative area of research since it offers alternative approaches to improve product quality and optimize machining processes regarding efficiency and economy. Current research at fraunhofer institute for machine tools and forming technology iwu focuses on facilitating the transfer of scientific knowledge to industrial solutions. Therefore, possible reasons preventing industrial application of adaptronic systems in cutting machines are identified and initial ideas to overcome these problems are presented.

关键词： machine tool Adaptive control Vibration assisted machining

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Process development and tooling design for intrinsic hybrid composites

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Journal of Physics: Conference Series 2017年第1期896卷

作者： M Riemer R Müller W G Drossel D Landgrebe Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Strasse 88 09126 Chemnitz www.iwu.fraunhofer.de

Hybrid parts, which combine the advantages of different material classes, are moving into the focus of lightweight applications. This development is amplified by their high potential for usage in the field of crash relevant structures. By the current state of the art, hybrid parts are mainly made in separate, subsequent forming and joining processes. By using the concept of an intrinsic hybrid, the shaping of the part and the joining of the different materials are performed in a single process step for shortening the overall processing time and thereby the manufacturing costs. The investigated hybrid part is made from continuous fibre reinforced plastic (FRP), in which a metallic reinforcement structure is integrated. The connection between these layered components is realized by a combination of adhesive bonding and a geometrical form fit. The form fit elements are intrinsically generated during the forming process. This contribution regards the development of the forming process and the design of the forming tool for the single step production of a hybrid part. To this end a forming tool, which combines the thermo-forming and the metal forming process, is developed. The main challenge by designing the tool is the temperature management of the tool elements for the variothermal forming process. The process parameters are determined in basic tests and finite element (FE) simulation studies. On the basis of these investigations a control concept for the steering of the motion axes and the tool temperature is developed. forming tests are carried out with the developed tool and the manufactured parts are analysed by computer assisted tomography (CT) scans.

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Manufacturing of hybrid aluminum copper joints by electromagnetic pulse welding – Identification of quantitative process windows

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AIP Conference Proceedings 2017年第1期1896卷

作者： Verena Psyk Christian Scheffler Maik Linnemann Dirk Landgrebe Fraunhofer Institute for Machine Tools and Forming Technology – IWU Reichenhainer Strasse 88 09126 Chemnitz Germany

Compared to conventional joining techniques, electromagnetic pulse welding offers important advantages especially when it comes to dissimilar material connections as e.g. copper aluminum welds. However, due to missing guidelines and tools for process design, the process has not been widely implemented in industrial production, yet. In order to contribute to overcoming this obstacle, a combined numerical and experimental process analysis for electromagnetic pulse welding of Cu-DHP and EN AW-1050 was carried out and the results were consolidated in a quantitative collision parameter based process window.

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Process simulation and experimental validation of Hot Metal Gas forming with new press hardening steels

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Journal of Physics: Conference Series 2017年第1期896卷

作者： A. Paul F. Reuther S. Neumann A. Albert D. Landgrebe Fraunhofer Institute for Machine Tools and Forming Technology (Fraunhofer IWU) Reichenhainer Straße 88 09126 Chemnitz Germany

One field in the work of the fraunhofer institute for machine tools and forming technology iwu in Chemnitz is industry applied research in Hot Metal Gas forming, combined with press hardening in one process step. In this paper the results of investigations on new press hardening steels from SSAB AB (Docol®1800 Bor and Docol®2000 Bor) are presented. Hot tensile tests recorded by the project partner (University of West Bohemia, Faculty of Mechanical Engineering) were used to create a material model for thermo-mechanical forming simulations. For this purpose the provided raw data were converted into flow curve approximations of the real stress-real strain-curves for both materials and afterwards integrated in a LS-DYNA simulation model of Hot Metal Gas forming with all relevant boundary conditions and sub-stages. Preliminary experimental tests were carried out using a tool at room temperature to permit evaluation of the forming behaviour of Docol 1800 Bor and Docol 2000 Bor tubes as well as validation of the simulation model. Using this demonstrator geometry (outer diameter 57 mm, tube length 300 mm, wall thickness 1.5 mm), the intention was to perform a series of tests with different furnace temperatures (from 870 °C to 1035 °C), maximum internal pressures (up to 67 MPa) and pressure build-up rates (up to 40 MPa/s) to evaluate the formability of Docol 1800 Bor and Docol 2000 Bor. Selected demonstrator parts produced in that way were subsequently analysed by wall thickness and hardness measurements. The tests were carried out using the completely modernized Dunkes/AP&T HS3-1500 hydroforming press at the fraunhofer iwu. In summary, creating a consistent simulation model with all relevant sub-stages was successfully established in LS-DYNA. The computation results show a high correlation with the experimental data regarding the thinning behaviour. The Hot Metal Gas forming of the demonstrator geometry was successfully established as well. Different hardness values could b

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Criteria for Energy-efficiency of Technological Processes, Technological machines and Production Engineering

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Procedia CIRP 2016年 46卷 340-343页

作者： A.P. Kuznetsov P. Blau H.-J. Koriath M. Richter Moscow State University of Technology “STANKIN” 127055 Moscow Russia Fraunhofer Institute for Machine Tools and Forming Technology IWU 09126 Chemnitz Germany

At present, a large number of methods for processing and forming of parts and products, technological processes and equipment have been created for their implementation. Trends towards improved productivity, accuracy, reliability, flexibility, economy of the technological process, technological machines and machine system demand the development of new methods for the analysis of their effectiveness. A unified approach to the assessment of the effectiveness of processes, equipment and production allows considering them as energy-information model in which there is a transformation of all types and forms of energy, matter and information. This allows considering the concept of “energy efficiency” as the relative coefficient of efficiency of the collection of all kinds of transformative mechanisms and devices. On the basis of the proposed energy-information model is given the generalized method for the evaluation and comparison of the integral energy efficiency of technological processes, technological machines and production engineering. Due to the directive for the ecodesign of energy-related products (2009/125/EC) and economic factors a metal cutting machine tool has been evaluated over its whole life cycle. A methodology of Life Cycle Impact Assessment (LCIA) was used to unfold the main ecological footprint. The energy consumption of the machine tool and in particular its components was measured for the manufacturing of a defined work piece. The results state priority resource saving potentials of the machine tool. Theoretical calculations and experimental evaluation are presented and compared in order to propose methods for industrial applications.

关键词： machine manufacturing process energy-information model energy efficiency criteria

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Towards Agile Engineering of Mechatronic Systems in machinery and Plant Construction

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Procedia CIRP 2016年 52卷 68-73页

作者： Thorsten P. Klein Gunther Reinhart Fraunhofer Institute for Machine Tools and Forming Technology (IWU) Project Group Resource-efficient Mechatronic Processing Machines Beim Glaspalast 5 86153 Augsburg Germany www.iwu.fraunhofer.de/rmv

Agile procedures (e.g. Scrum) are commonly used in rapidly changing environments of software engineering. Experts appreciate improvements in interdisciplinary collaboration, lead times and development costs by applying agile techniques as artifacts, meetings, roles and visualisation methods. Up to now, the use of agile procedures is still limited to IT-projects, due to a lack of profound knowledge in transferring agile techniques into interdisciplinary projects. This contribution presents the research work on Agile Engineering, a counterpart of Lean Product Development, by the systematic integration of agile techniques into the development process of mechatronic production systems. Thereto, an introduction and state of the art is given concerning the industry sector of machinery and plant construction as well as agile methodologies. The main focus of the paper is represented by the classification and comparison of Agile Engineering as well as the main features of integrating agile techniques into the mechatronic engineering process. According to the advanced research insights of the last years, Agile Engineering is a new enabler of success for establishing an agile production, providing promising approaches for coping with change and uncertainty efficiently.

关键词： Agility Mechatronics Engineering Process Lean Product Development Scrum

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Simulation-based Correction Approach for Thermo-elastic Workpiece Deformations During Milling Processes

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Procedia CIRP 2016年 46卷 103-106页

作者： J. Glänzel R. Herzog S. Ihlenfeldt A. Meyer R. Unger Fraunhofer Institut for Machine Tools and Forming Technology IWU Chemnitz Germany Technische Universität Chemnitz Chemnitz Germany Technische Universität Dresden Dresden Germany

Based on the method of adaptive finite elements (FEM) a correction approach has been considered to identify the influence of thermo-elastic workpiece deformations during the production process milling. The paper presents a simulation-based tolerance variation calculation of cutting paths, which is caused by the heat input of the machine tool. Therefore a mathematical method is developed to numerically depict the progress of the miller with different curves A(t), B(t) and C(t). These curves are used to map the state of the milling path during the production process as well as to compare the current workpiece contour and the target workpiece contour. The tool center point (TCP) correction results from mapping of time-dependent deformation fields from the FE simulation. The aim is, on the one hand, to make statements before the production about keeping the tolerance, and on the other hand, to derive other correction approaches for the adaption of the cutting path coordinates.

关键词： milling tolerancing material removal thermo-elastic adaptive FEM

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