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Influence of different cooling strategies during hard turning of AISI 52100 - part I: thermo-mechanical load, tool wear, surface topography and manufacturing accuracy

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Procedia CIRP 2020年 87卷 77-82页

作者： Stephan Basten Benjamin Kirsch Werner Ankener Marek Smaga Tilmann Beck Julian Uebel Jörg Seewig Jan C. Aurich Institute for Manufacturing Technology and Production Systems TU Kaiserslautern Gottlieb-Daimler-Str. 67663 Kaiserslautern Germany Institute of Materials Science and Engineering TU Kaiserslautern Gottlieb-Daimler-Str. 67663 Kaiserslautern Germany Institute for Measurement and Sensor Technology TU Kaiserslautern Gottlieb-Daimler-Str. 67663 Kaiserslautern Germany

This paper presents a characterization of the turning process for finishing of AISI 52100 in martensitic heat treatment state at various cooling conditions. With regard to the cooling conditions, LN 2 -cooling, CO 2 snow cooling at varied mass flows, sub-zero metalworking fluids (MWF) at varied supply temperatures, and dry machining were examined. The tool temperatures, the process forces, the tool wear, the surface topography as well as the dimensional deviations of the workpiece caused by unintended alterations of the depth of cut due to a thermal expansion or contraction of the workpiece are analyzed. The application of MWF supplied at 20 °C results in an unchanging thermo-mechanical load in the tool-work interface and surface topography as well as in a high manufacturing accuracy. Dry machining leads to an increasing depth of cut of up to 10 %, resulting in radial dimensional errors. Cryogenic machining and using the sub-zero MWF supplied at -30 °C exhibit a different behavior due to high cooling effects: the depth of cut is reduced up to 10 %, also leading to radial dimensional errors. However, even though the depth of cut and thus the undeformed chip cross section is affected by up to 10 % depending the cooling condition, the mechanical load remains approximately constant during single cuts. In part II, the surface and near surface microstructure morphology of the workpieces is characterized.

关键词： cryogenic turning surface integrity accuracy error hard machining precicion turning

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Mechanical properties of an adjustable weighing cell prototype 19

Mechanical properties of an adjustable weighing cell prototy...

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19th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2019

作者： Darnieder, Maximilian Pabst, Markus Fröhlich, Thomas Zentner, Lena Theska, René Department of Mechanical Engineering Technische Universität Ilmenau Institute for Design and Precision Engineering Precision Engineering Group Department of Mechanical Engineering Technische Universität Ilmenau Institute for Process Measurement and Sensor Technology Process Measurement Technology Group Germany Department of Mechanical Engineering Technische Universität Ilmenau Compliant Systems Group Germany

ISBN: (纸本)9780995775145

Weighing cells based on the principle of electromagnetic force compensation are highly sensitive force measuring devices. A compliant mechanism with thin flexure hinges constitutes the mechanical basis of the balance. The weighing cells are the core components of high-performance vacuum mass comparators, e.g. for the comparison of one kilogram mass standards. According to the mechanical models, the achievable sensitivity of the measurement device is only limited by the adjustment resolution. Without further measures, the vertical adjustment of small trim masses represents a trade-off between resolution and tilt sensitivity. The numerical test of the underlying adjustment concept by finite element models reveals that the objectives of a high sensitivity and a low tilt sensitivity can be achieved simultaneously by a meaningful combination of adjustment measures. This represents a promising concept for the further enhancement of vacuum mass comparators. The prototypes are planar weighing cell structures for a flexible choice of the manufacturing process. The planar mechanism facilitates the comparison between models and measurements. The weighing cells for a nominal mass of 300g are experimentally investigated. The measurement of tilt reactions is enabled by the use of a precision tilt table as base for the weighing cell. Properties like stiffness and tilt sensitivity are determined as a function of the adjustment parameters. This way the mechanical models are verified, and the property enhancement of the weighing cell is evaluated. © 2019 European Society for Precision Engineering and Nanotechnology, Conference Proceedings - 19th International Conference and Exhibition, EUSPEN 2019. All rights reserved.

关键词： Cells

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Frequency Band Broadening and Charge Density Enhancement of a Vibrational Triboelectric Nanogenerator with Two Stoppers

SSRN

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SSRN 2022年

作者： Qi, Youchao Liu, Guoxu Kuang, Yang Wang, Lu Zeng, Jianhua Lin, Yuan Zhou, Han Zhu, Meiling Zhang, Chi CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and Sensor Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Beijing101400 China College of Engineering Mathematics and Physical Sciences University of Exeter ExeterEX4 4QF United Kingdom School of Nanoscience and Technology University of Chinese Academy of Sciences Beijing100049 China State Key Laboratory for Manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technologies Collaborative Innovation Center of Suzhou Nano Science and Technology Xi’an Jiaotong University Xi’an710049 China Center on Nanoenergy Research School of Physical Science and Technology Guangxi University China

Vibrational triboelectric nanogenerators (V-TENG) can be used to harvest broadband vibration energy due to the nonlinear impact force induced by a stopper. However, V-TENGs with a single stopper have limited bandwidth and surface charge density, which has limited their application in wideband vibration energy harvesting. Herein, a V-TENG with two stoppers is proposed for frequency band broadening and charge density enhancement. The theoretical analysis and experimental validation have indicated the V-TENG with two stoppers could improve the bandwidth by 75% compared with one stopper at a gap distance of 0.5 mm. Moreover, a charge pump can be constructed with two output channels, which has improved surface charge density by about 14 times. With the frequency varying from 18 to 38 Hz, the V-TENG can continually power 400 LEDs and charge a commercial capacitor quickly. This work has shown an encouraging method for enhancing the performance of V-TENGs, which also has great prospects in harvesting wideband vibration energy from machines, cars, ships, and human motions for self-powered electronics. © 2022, The Authors. All rights reserved.

关键词： Nanogenerators

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Tracking of Magnetic Micromotors in Confined Channels Through Scattering Tissue

Tracking of Magnetic Micromotors in Confined Channels Throug...

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IEEE International Conference on Nano/Molecular Medicine and Engineering (NANOMED)

作者： Azaam Aziz Dmitriy Karnaushenko Nektarios Koukourakis Jürgen W. Czarske Oliver G. Schmidt Mariana Medina-Sánchez Institute for Integrative Nanosciences Leibniz Institute for Solid State and Materials Research Dresden Germany Chair of Measurement and Sensor System Technique and Competence Center BIOLAS TU Dresden School of Engineering Dresden Germany Cluster of Excellence Physics of Life TU Dresden Germany and Faculty of Physics School of Science Dresden TU Germany Professorship of Material Systems for Nanoelectronics Chemnitz University of Technology Chemnitz Germany

ISBN: (纸本)9781665458573

The field of small-scale microdevices is growing rapidly towards the development of tethered/untethered microsensors and therapeutic agents that can move through narrow vascular networks in living organisms to diagnose and treat for example vascular diseases. However, imaging and localization of such microdevices are challenging under scattering tissue due to the lack of high spatial and temporal resolution that compromises the penetration depth and therefore the application scenario. Here, we report the tracking of magnetically-driven rolling micromotors (20 µm in diameter) through scattering tissue (1.2 mm thickness) using reflective infrared (IR) imaging. This technique provides high spatiotemporal resolution for the tracking of micro-agents in a narrow vascular network. As a potential application, we suggest the use of such micro-agents as micro-viscosimeters, in which by analyzing their dynamics, one can extract some basic information on the surrounding fluid properties which might be related to certain health status.

关键词： Stimulated emission Fluid dynamics Scattering Optical imaging Spatiotemporal phenomena Optical scattering Optical reflection

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Scanning Acoustic Microscopy for Quantifying Two-phase Transfer in Operando Alkaline Water Electrolyzer

arXiv

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arXiv 2024年

作者： Dou, Zehua Rox, Hannes Ramos, Zyzi Baumann, Robert Ravishankar, Rachappa Czurratis, Peter Yang, Xuegeng Lasagni, Andrés Fabian Eckert, Kerstin Czarske, Juergen Weik, David Faculty of Electrical and Computer Engineering Laboratory of Measurement and Sensor System Technique Technische Universität Dresden Helmholtzstraße 18 Dresden01069 Germany Institute of Fluid Dynamics Helmholtz-Zentrum Dresden-Rossendorf Bautzner Landstraße 400 Dresden01328 Germany PVA TePla Analytical Systems GmbH Deutschordenstraße 38 Westhausen73463 Germany Institute of Manufacturing Science and Engineering Technische Universität Dresden George-Baehr-Straße 3c Dresden01069 Germany Fraunhofer Institute for Material and Beam Technology IWS Winterbergstraße 28 Dresden01277 Germany Institute of Process Engineering and Environmental Technology Technische Universität Dresden Helmholtzstraße 14 Dresden01069 Germany Hydrogen Lab School of Engineering Technische Universität Dresden Helmholtzstraße 14 Dresden01062 Germany Institute for Emerging Electronic Technologies Leibniz Institute for Solid State and Materials Research Dresden Helmholtzstraße 20 Dresden01069 Germany

Improved understandings of two-phase transport in electrochemical gas-evolving systems are increasingly demanded, while high-performance imaging techniques using simplified instrumentations are not readily available. This work presents volumetric scanning acoustic microscopy (SAM) imaging for quantifying the dynamics of gas bubbles and electrolyte in porous Nickel electrodes with different wettability and structures during alkaline water electrolysis (AWE). We realize high-resolution 3D imaging at 10's µm level using high frequency spherically focused ultrasound. The high resolution allowed us to clearly visualize the spatial distributions of produced bubbles in the porous electrodes over time. Moreover, we are able to quantify the residual gas volume in an electrode and its coverage due to bubble evolution, which dominate its transport overpotential. Taking these advantages, we elucidate the impacts of electrodes' wettability and structures on their electrolysis performance, on a regular laboratory base. The obtained knowledge provides us important optimization guidelines of AWE designs and operating schemes. Copyright © 2024, The Authors. All rights reserved.

关键词： Mass transfer

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Micro- And nanofabrication technologies using the nanopositioning and nanomeasuring machines 11

Micro- And nanofabrication technologies using the nanopositi...

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Optical measurement systems for Industrial Inspection XI 2019

作者： Weidenfeller, Laura Hofmann, Martin Kirchner, Johannes Supreeti, Shraddha Rangelow, Ivo W. Sinzinger, Stefan Manske, Eberhard Ilmenau University of Technology Institute for Process Measurement and Sensor Technology Gustav-Kirchhoff-Str. 1 Ilmenau Germany Ilmenau University of Technology Department of Micro- and Nanoelectronic Systems Gustav-Kirchhoff-Str. 1 Ilmenau Germany Ilmenau University of Technology Department of Microsystems Technology Max-Planck-Ring 12 Ilmenau Germany Ilmenau University of Technology Department of Technical Optics Helmholtzring 1 Ilmenau Germany

ISBN: (数字)9781510627925

ISBN: (纸本)9781510627918

To keep up with Moore's law in future, the critical dimensions of device features must further decrease in size. Thus, the nano-electronics and nano-optics manufacturing is based on the ongoing development of the lithography and encompasses also some unconventional methods. In this context, we use the Nanopositioning and Nanomeasuring Machine (NPMM) to generate features in resist layers by means of Direct Laser Writing (DLW),1 Field Emission Scanning Probe Lithography (FE-SPL)2 and Soft UV-Nanoimprint Lithography (Soft UV-NIL)3 with highest accuracy. The NPMM was collaboratively developed by TU Ilmenau and SIOS Meßtechnik GmbH.4 The tool provides a large positioning volume of 25 mm × 25 mm × 5 mm with a positioning resolution of 0.1 nm and a repeatability of less than 0.3 nm over the full range. Previously a single electron transistor (SET) working at room temperature generated by FE-SPL has been demonstrated.5 However, the throughput is limited because of the serial writing scheme making Tennant's law (At ∼R5) valid.6 Here, At is the areal throughput and R the lithographic resolution. Thus, patterning of the whole NPMM positioning area by FE-SPL is very time consuming. In order to address this problem, different strategies and/or combinations are conceivable. In this work a so-called Mix-and-Match lithography is conducted. A fast generation of structures in the sub-micron range is possible by means of DLW. By this, features such as electrical wires, contact patches for bonding or labels are generated in resist. Subsequently, we use FE-SPL in order to define the actual nano-scaled features for quantum or single electron devices. In combination, DLW and FE-SPL are maskless lithography strategies, hence, offering completely novel opportunities for rapid nanoscale prototyping of largescale resist patterns. An explanation of this technique is given in a previous publication.7 Furthermore, after reactive ion etching, the sample can be used as template for Soft UV-NIL, th

关键词： Single electron transistors

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Trans-scale Nanofabrication with Nanopositioning and Nanomeasuring Machines

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IFAC-PapersOnLine 2019年第15期52卷 151-156页

作者： Andreas Meister Laura Weidenfeller Johannes Kirchner Martin Hofmann Rostyslav Mastylo Roland Füßl Johann Reger Eberhard Manske Institute for Process Measurement and Sensor Technology Technische Universität Ilmenau Germany Institute for Automation and Systems Engineering Technische Universität Ilmenau Germany Institute of Microelectronics and Nanoelectronics Technische Universität Ilmenau Germany

Nanofabrication in macroscopic working areas addresses the manipulation with nanometer precision in large scale working areas of several hundred millimeters. In order to reduce the fabrication time of large objects, high dynamic position tracking is required. The position and orientation of the nanopositioning and nanomeasuring machine have to be controlled permanently to compensate external disturbances like ground motion, sound waves, et cetera. Many applications have strict demands on following the track, e.g. to reduce the line roughness. High performant data and signal processing and efficient control algorithms are required to overcome these challenges. This work presents the nanopositioning and measuring machine as well as the utilized control system. Several scanning and fabrication experiments have been carried out in order to demonstrate the performance of the setup.

关键词： Precision systems, Micro-/Nanosystems sensors measurement systems

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Feature-Aided Multitarget Tracking for Optical Belt Sorters

Feature-Aided Multitarget Tracking for Optical Belt Sorters

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International Conference on Information Fusion

作者： Tobias Kronauer Florian Pfaff Benjamin Noack Wei Tiant Georg Maier Uwe D. Hanebeck Intelligent Sensor-Actuator-Systems Laboratory (ISAS) Karlsruhe Institute of Technology (KIT) Germany Institute of Measurement and Control Systems (MRT) Karlsruhe Institute of Technology (KIT) Germany Fraunhofer Institute of Optronics System Technologies and Image Exploitation (IOSB) Germany

ISBN: (数字)9780996452786

ISBN: (纸本)9781728118406

Industrial optical belt sorters are highly versatile in sorting bulk material or food, especially if mechanical properties are not sufficient for an adequate sorting quality. In previous works, we could show that the sorting quality can be enhanced by replacing the line scan camera, which is normally used, with an area scan camera. By performing multitarget tracking within the field of view, the precision of the utilized separation mechanism can be enhanced. The employed kinematics-based multitarget tracking crucially depends on the ability to associate detection hypotheses of the same particle across multiple frames. In this work, we propose a procedure to incorporate the visual similarity of the detected particles into the kinematics-based multitarget tracking that is generic and evaluates the visual similarity independent of the kinematics. For evaluating the visual similarity, we use the Kernelized Correlation Filter, the Large Margin Nearest Neighbor method and the Normalized Cross Correlation. Although no clear superiority for any of the visual similarity measures mentioned above could be determined, an improvement of all considered error metrics was attained.

关键词： Visualization Target tracking Cameras Atmospheric measurements Particle measurements Kernel Training

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Approach for the observation of surface conditions in-process by soft sensors during cryogenic hard turning

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Procedia CIRP 2019年 81卷 1260-1265页

作者： Julian Uebel Felix Ströer Stephan Basten Werner Ankener Hendrik Hotz Lukas Heberger Gerhard Stelzer Benjamin Kirsch Marek Smaga Jörg Seewig Jan C. Aurich Tilmann Beck Institute for Measurement and Sensor-Technology Gottlieb-Daimler-Str. 44 67663 Kaiserslautern Germany Institute for Manufacturing Technology and Production Systems Gottlieb-Daimler-Str. 44 67663 Kaiserslautern Germany Institute of Materials Science and Engineering Gottlieb-Daimler-Str. 44 67663 Kaiserslautern Germany

Even though required for a robust production, direct measurement of the surface condition in-process is a challenge due to technical limitations. A concept for in-process monitoring of surface conditions like hardness or microtopography using observer-like structures will be discussed in this paper from a metrological point of view. Initially, the background regarding manufacturing and material sciences is summarized. Afterwards, the problem is analysed from a control engineering point of view and challenges and solutions are discussed. Finally, a concept for a new sensor, the opto-pneumatic scattered light sensor, is presented, which contributes to the indirect measurement of the microtophography in-process.

关键词： soft-sensor surface condition in-process indirect measurement opto-pneumatic scattered light sensor

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A GaN 500 kHz High Current Active Clamp Phase-Shifted Full-Bridge Converter with Zero-Voltage Switching over the Entire Line and Load Range 20

A GaN 500 kHz High Current Active Clamp Phase-Shifted Full-B...

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20th European Conference on Power Electronics and Applications, EPE 2018 ECCE Europe

作者： Heintze, Martin Stefan Butzmann, Ing. Robert Bosch GmbH Frankfurter Str. Tamm871732 Germany University of Wuppertal Sensor Technology and Measurement-Technology Systems Campus Freudenberg Rainer-Gruenter-Str. 21 Wuppertal42119 Germany

ISBN: (纸本)9789075815283

A GaN Active Clamp Phase-Shifted Full-bridge (PSFB) is introduced which enables zero-voltage switching (ZVS) over entire load and voltage range without any additional auxiliary circuit elements. For high load operation ZVS is achieved through a small leakage inductance as in conventional PSFB converters. To expand the ZVS range to zero load conditions the ripple current of the current doubler inductor in conjunction with an increased magnetizing current of the main transformer is used to obtain ZVS in every operating point. A secondary active clamp circuit limits the over-voltage of the current doubler rectifier. The ZVS mechanism is discussed in detail and some design tradeoffs are highlighted. The ability of the proposed circuit is demonstrated using a 1.5 kW, 400 V to 12 V DC/DC converter for automotive application with a wide voltage and power range. The small leakage inductance together with the ability to realize soft switching even under low load conditions enables a significant increase of the switching frequency up to 500 kHz and thus a remarkable increase of power density with very high efficiency. © 2018 EPE Association.

关键词： Timing circuits

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