检索结果-内蒙古大学图书馆

12th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2012

作者： Schubert, Andreas Zeidler, Henning Wolf, Nicolas Hackert-Oschätzchen, Matthias Schneider, Jörg Chemnitz University of Technology Department of Micromanufacturing Technology Reichenhainer Str. 70 Chemnitz09107 Germany Fraunhofer Institute for Machine Tools and Forming Technology IWU Department Micro- and High-Precision Manufacturing Reichenhainer Str. 88 Chemnitz09126 Germany

ISBN: (纸本)9780956679000

Ultrasonic vibration has been found very beneficial for the micro electro discharge machining (μEDM) of deep microstructures with high aspect ratios. In this study, the discharge properties of μEDM aided with direct ultrasonic workpiece vibration are analysed and compared to conventional μEDM machining. It can be shown that not only the number of discharges per second is significantly improved, but also the typical height of the discharge current is differently distributed. The investigation shows that the amount of open circuit states in μEDM can be noticeably reduced by using ultrasonic vibration assistance.

关键词： Ultrasonic effects

来源：评论

学校读者我要写书评

暂无评论

Model-based position control of Shape memory alloy actuators

引用

International Journal of Mechatronics and Manufacturing Systems 2012年第2期5卷 93-105页

作者： Neugebauer, Reimund Pagel, Kenny Bucht, Andre Drossel, Welf-Guntram Department of Adaptronics and Acoustics Fraunhofer Institute for Machine Tools and Forming Technology Nöthnitzer Straße 44 01187 Dresden Germany

Shape-memory-alloys (SMAs) are easy to integrate into mechanical structures and capable of handling high specific workloads. Therefore, SMAs possess an outstanding potential to serve as positioning devices in various applications. We present here the multi-domain modelling of an electrically heated SMA wire which includes changes of electrical parameters in conjunction to mechanical parameters. Due to the correlation between electrical resistance and mechanical stroke, it was possible to implement a resistance-based position control without the necessity of an external positioning sensor. In order to design a linear position controller by common rules, the highly complex and non-linear model was simplified. Controller development yielded a PID algorithm that was implemented on a rapid prototyping system as part of an SMA wire test bench. The models accuracy was verified by various measurements with different wires and multiple loads. Based on that, it was possible to design an actuator which utilises a flexible socket instead of fixed mountings. Copyright © 2012 Inderscience Enterprises Ltd.

关键词： Position control

来源：评论

学校读者我要写书评

暂无评论

Multi-scale structures for influencing the tribological properties of metallic surfaces

Multi-scale structures for influencing the tribological prop...

引用

ASPE 2011 Spring Topical Meeting on Structured and Freeform Surfaces

作者： Neugebauer, Reimund Schubert, Andreas Avila, Miguel Sylla, David Schmidt, Torsten Institute for Machine Tools and Production Processes TU Chemnitz 09112 Chemnitz Germany Department of Precision Technology and Micromanufacturing Fraunhofer Institute for Machine Tools and Forming Technology 09126 Chemnitz Germany

来源：评论

学校读者我要写书评

暂无评论

Structuring of tribological active surfaces for reduction of frictional losses 11

Structuring of tribological active surfaces for reduction of...

引用

11th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2011

作者： Schubert, A. Edelmann, J. Sylla, D. Hackert-Oschätzchen, M. Fraunhofer Institute for Machine Tools and Forming Technology IWU Chemnitz Germany Department of Micromanufacturing Technology Chemnitz University of Technology Chemnitz Germany

ISBN: (纸本)9780955308291

Surfaces in a wide range of engineering applications are subject to tribological loads. Many of these surfaces have a profound effect on the efficiency of manufacturing processes and products during service. This paper focuses on the effect of surface microstructure geometry on the friction coefficient between lubricated sliding partners. Initially, the Computational Fluid Dynamics (CFD) package COMSOL Multiphysics was used to determine the effect of geometry parameters of semi-spherical cavities on hydrodynamic pressure. The simulations showed that surface microstructures act as micro pressure chambers that would allow the sliding partners to reach hydrodynamic lubrication at lower operating speeds. Patterns of the microstructure that showed the highest pressure build-up in the simulations were then manufactured by Jet-ECM and tested in a tribometer. It was determined that patterned spherical segment cavities 10 μm deep and 500 μm wide yield a friction coefficient reduction of up to 35 %.

关键词： Multiphysics

来源：评论

学校读者我要写书评

暂无评论

Influence of kinematics on the surface integrity in orthogonal turn-milling of aluminium matrix composites 11

Influence of kinematics on the surface integrity in orthogon...

引用

11th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2011

作者： Schubert, A. Funke, R. Nestler, A. Micromanufacturing Technology Department of Mechanical Engineering Chemnitz University of Technology Chemnitz09107 Germany Fraunhofer Institute for Machine Tools and Forming Technology Chemnitz09126 Germany

ISBN: (纸本)9780955308291

This paper deals with the investigation of orthogonal turn-milling of aluminium matrix composites using CVD (chemical vapour deposition) diamond tipped end mills. The influence of eccentricity, tool position and milling strategy on the surface integrity is described. The results show that the lowest roughness values can be achieved by positioning the tool below the work piece axis, using an eccentricity e = 2.5 mm and choosing up milling.

关键词： Chemical vapor deposition

来源：评论

学校读者我要写书评

暂无评论

Precision turning with localized anodic dissolution 11

Precision turning with localized anodic dissolution

引用

11th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2011

作者： Hackert-Oschätzchen, M. Meichsner, G. Zinecker, M. Schubert, A. Department Micromanufacturing Technology Faculty of Mechanical Engineering Chemnitz University of Technology Chemnitz09107 Germany Fraunhofer Institute for Machine Tools and Forming Technology Chemnitz09126 Germany

ISBN: (纸本)9780955308291

The basic principle of Electrochemical Machining is an anodic dissolution of metallic work pieces at their interface to a liquid ion conductor, called electrolyte, under the influence of electric charge transport. Electrochemical Machining with closed electrolytic free jet (Jet-ECM) is a new procedure which applies high current densities with a high degree of local removal, high localization of erosion and high surface quality [1]. Starting from this point machining of rotating work pieces by help of Jet-ECM is investigated [2]. Therefore a Jet-EC Turning prototype system was developed at Chemnitz University of technology. In this study experimental investigations for a characterization of the influence of different process parameters on the Jet-EC turning result are presented.

关键词： Electrolytes

来源：评论

学校读者我要写书评

暂无评论

Virtual reality-aided planning for energy-autonomous factories

Virtual reality-aided planning for energy-autonomous factori...

引用

IEEE International Conference on Industrial Informatics (INDIN)

作者： Reimund Neugebauer Franziska Pürzel Antje Schreiber Tino Riedel Fraunhofer Institute for Machine Tools and Forming Technology IWU Chemnitz Germany Department of Machine Tools and Forming Technology Institute for Machine Tools and Production Processes IWP Chemnitz University of Technology Germany

The consideration of energy-related parameters is already in the planning phase an important step towards an energy-autonomous factory. Using Virtual Reality (VR) gives planners an important basis for decision-making with regards to drafting the layout. This potential should also be used for incorporating energy-related parameters. This paper introduces the coupling of a 2D planning system with a VR environment as the basis for the development of an energy-sensitive planning system. A prerequisite for considering energy-related parameters is recording and visualizing them. Therefore, the second part of the paper deals with energy visualization within a machine at the micro level.

关键词： Planning Production facilities Layout Visualization Software machine tools

来源：评论

学校读者我要写书评

暂无评论

Micro - EDM: Process effects on the tool wear ratio 11

Micro - EDM: Process effects on the tool wear ratio

引用

11th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2011

作者： Schubert, A. Wolf, N. Zeidler, H. Fraunhofer Institute for Machine Tools and Forming Technology IWU Department Micro- and High-Precision Manufacturing Reichenhainer Str. 88 Chemnitz09126 Germany Chemnitz University of Technology Department Micromanufacturing Technology Chemnitz09107 Germany

ISBN: (纸本)9780955308291

The fabrication of high aspect ratio microstructures is very challenging, especially when the work piece material is hard to machine. Electro Discharge Machining (EDM) offers a contact- and nearly force free way of micromachining and is therefore an appropriate means to producing microstructures. One key obstacle for a precise machining by micro-EDM is the tool wear. When ED-machining microstructures process speed, stability and thus tool wear are related to the aspect ratio of the structures. In this study, tool wear ratio within different stages of the EDM process is analysed when machining high aspect ratio micro bores in steel. Experiments with bores of different depths show the correlation between the stage of the process and the flushing conditions on the one hand and the tool wear ratio on the other hand. Thus, it is possible to find and apply optimized parameters for the different process stages. A better understanding of the tool wear will help to minimize it, reducing the cost of the tools and enhancing the precision of the process. This also shall allow an enhancement of the process speed because the need for flushing material out of the bore is reduced by the amount of tool material that can be saved.

关键词： Micromachining

来源：评论

学校读者我要写书评

暂无评论

Efficient Reduced Order State Space Model Computation for a Class of Second Order Index One Systems

引用

PAMM 2012年第1期12卷

作者： Peter Benner Burkhard Kranz Jens Saak M. Monir Uddin Max Planck Institute for Dynamics of Complex Technical Systems Sandtorstraße 1 D-39106 Magdeburg Mathematics in Industry and Technology Department of Mathematics Chemnitz University of Technology Reichenhainer Str. 41 D-09126 Chemnitz Fraunhofer for Machine Tools and Forming Technology (IWU) Nöthnitzer Straße 44 D-1187 Dresden

Simulation, design optimization and controller design of modern machine tools heavily rely on adequat numerical models. In order to achieve results in shorter computation times, reduced order models (ROMs) are applied in either of these tasks. Most modern simulation tools expect these ROMs to come in standard state space form. Structural models of the machine tool are however of second order type. In case piezo actuators are used in the device they are even differential algebraic equations (DAEs) of index one due to the coupling to the equations describing the electric potentials. This contribution is dedicated especially to those systems. We combine the ideas for balanced truncation model order reduction of large and sparse index 1 DAEs with methods developed for the efficient numerical handling of second order systems. (© 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)

关键词：

来源：评论

学校读者我要写书评

暂无评论

Approaches to enhance surface integrity in turning of aluminium matrix composites 10

Approaches to enhance surface integrity in turning of alumin...

引用

10th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2010

作者： Schubert, A. Nestler, A. Department in Micromanufacturing Technology Chemnitz University of Technology Germany Fraunhofer Institute for Machine Tools and Forming Technology Germany

ISBN: (纸本)9780955308284

Aluminium matrix composites are innovative lightweight construction materials, which usually consist of a relatively soft and ductile matrix and a hard ceramic reinforcing component. The high hardness of the reinforcing component results in extensively increased cutting tool wear by abrasion as well as defects of the machined surface in the form of voids and scaling. In this study, turning tests were conducted on Al2O3 particle-reinforced aluminium to evaluate the effect of tool edge geometry on cutting performance and surface integrity. These investigations have shown a significant reduction of the roughness and surface defects using tools with appropriate rake geometries. © euspen Headquarters.

关键词： Surface defects

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：