检索结果-内蒙古大学图书馆

15th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2015

作者： Schubert, Andreas Zeidler, Henning Flemmig, Sebastian Penzel, Michael Krönert, Maik Meichsner, Gunnar Essel, Shai Prof. Micromanufacturing Technology Technische Universität Chemnitz Chemnitz09107 Germany Fraunhofer Institute for Machine Tools and Forming Technology Chemnitz09126 Germany Israel Institute of Metals Technion Haifa Israel

ISBN: (纸本)9780956679079

To increase the efficiency of heat transfer and cooling systems, high thermally conductive materials have to be developed. Using Aluminium reinforced by Diamond particles, thermal conductivity and heat dissipation can be enhanced in correspondence to particle size. Due to the high hardness of diamond the machinability decreases. A cutting machining process is not feasible because of the high tool wear. In this study two possible ablating techniques, Pulsed Electrochemical Machining (PECM) and Micro Electro Discharge Machining (μEDM) are assessed. It is shown that with both methods machining and shaping of AMCs, reinforced by monocrystalline diamonds, is possible. Due to the chemical stability of the diamond particles only the base material of Aluminium has been electrochemical machined. Similar to PECM, and also for μEDM, ablating is a selective machining process, but here an approach for further ablating possibilities is given. The achieved surface roughness is dependant on the particle size of the Diamond.

关键词： Thermal conductivity

来源：评论

学校读者我要写书评

暂无评论

Resource Networks: Decentralised Factory Operation Utilising Renewable Energy Sources

引用

Procedia CIRP 2015年 26卷 486-491页

作者： Johannes Stoldt Enrico Franz Andreas Schlegel Matthias Putz Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Strasse 88 09126 Chemnitz Germany

Striving for sustainability, most industrialised countries make increasing use of renewable energy sources to meet their energy demands. This causes power generation to become more decentralised and volatile, making flexibility in production (i.e. energy demand) a fundamental necessity for manufacturing companies. Hence, it is to be expected that companies which attain a symbiosis of renewable energy applications, efficient technologies, and innovative approaches to production organisation will have a competitive advantage in the future. The EU funds research in this direction as part of the REEMAIN project, amongst others. In particular, a concept for Resource Networks is developed. These networks aim to manage production using renewable energy sources by dividing a complex factory into smaller subsystems including energy suppliers and consumers, as well as storages to reach this symbiosis. This paper explains the concept and its application within fraunhofer IWU's E 3 -Research Factory.

关键词： Energy efficiency Manufacturing system Production Renewable energy sources Sustainable development

来源：评论

学校读者我要写书评

暂无评论

Effects of Different Cutting Edge Preparation Methods on Micro Milling Performance

引用

Procedia CIRP 2016年 46卷 352-355页

作者： E. Uhlmann D. Oberschmidt Y. Kuche A. Löwenstein I. Winker Institute for Machine Tools and Factory Management (IWF) Technische Universität Berlin Pascalstraße 8–9 10587 Berlin Germany Fraunhofer Institute for Production Systems and Design Technology (IPK) Pascalstraße 8–9 10587 Berlin Germany

In micro milling, which is mostly used in mold and die making, process reliability and predictability of tool failure are important. Particularly in precision and micro machining, tool breakage is hardly detectable and the requirements on accuracy are very high. Immersed tumbling is an appropriate process for the defined cutting edge preparation of micro milling tools. Its effects like increasing tool wear performance and tool life has been evaluated. In this paper, different cutting edge preparation processes showed that in cutting tests different effects occur regarding tool wear, process forces and surface quality. Immersed tumbling leads to the lowest active force F a , but magnet finishing leads still do a slightly better surface quality.

关键词： Cutting edge preparation micro milling process reliability

来源：评论

学校读者我要写书评

暂无评论

Influence of Cutting Edge Preparation on the Performance of Micro Milling tools

引用

Procedia CIRP 2016年 46卷 214-217页

作者： E. Uhlmann D. Oberschmidt A. Löwenstein Y. Kuche Institute for Machine Tools and Factory Management (IWF) Technische Universität Berlin Pascalstraße 8-9 10587 Berlin Germany Fraunhofer Institute for Production Systems and Design Technology (IPK) Pascalstraße 8-9 10587 Berlin Germany

A main reason for premature tool failure in micro milling is the irregular wear behavior of the cutting tools. An approach to improve the tool wear behavior is a defined cutting edge preparation using immersed tumbling. A particular challenge is the cutting edge preparation of micro milling tools with small diameters D ≤ 0.5 mm. High loads within the preparation process can lead to outbreaks of the cutting edge and tool breakage. Furthermore, the influence of changed cutting edge geometry regarding the process behavior has to be more examined for these tool diameters. In this paper, micro milling tools with a diameter D = 0.2 mm will be prepared and the influence on the cutting process will be presented and discussed. The experiments will show a better wear behavior for the prepared tools and an improved surface roughness on the machined workpiece.

关键词： micro milling cutting edge wear machining

来源：评论

学校读者我要写书评

暂无评论

Improving the ramp-up process of a body-construction line by numerical supported design of clamping devices and FEM based tolerance prognosis 18th

Improving the ramp-up process of a body-construction line by...

引用

18th International ESAFORM Conference on Material forming, ESAFORM 2015

作者： Landgrebe, Dirk Ackert, Patrick Grützner, Raik Weber, Johannes Mauermann, Reinhard Tegtmeier, André Fraunhofer Institute for Machine Tools and Forming Technology Nöthnitzer Straße 44 Dresden01187 Germany Porsche Leipzig GmbH Porschestraße 1 Leipzig04158 Germany

ISBN: (纸本)9783038354710

Car body manufacturing begins with sheet metal forming, while in subsequent steps the inner structures of the vehicle are assembled and connected to the outer skin by hemming. The use of FEM (finite element method) to assistant in ramp-up processes of car body construction lines is increasing, thanks to developments in recent years. Several methods to predict the distortion of joining and the dimensional effect of clamping during the assembly process were presented and validated. Dimensional effects of the clamping process are basically the result of a deliberate alignment, other than the given values of construction to compensate dimensional inaccuracy of single parts from the body shop. These deliberate alignments are generally effected through a translation of clamps and pins in the clamping device. Until now, most of the methods of clamping and joining simulation presented have been verified using academic samples. In this report, the quality of forecasting in real problems during a ramp-up process will be verified and expanded. As part of a national project, co-funded by Sächsische Aufbaubank (SAB), the potential of FEM to assist in the ramp-up process were reviewed in a cooperative effort between Porsche Leipzig GmbH and fraunhofer institute for machine tools and forming technology (IWU). Furthermore, it will be shown that developed methods are able to represent the influence of deliberate positioning of clamps in complex samples. © (2015) Trans Tech Publications, Switzerland.

关键词： Finite element method

来源：评论

学校读者我要写书评

暂无评论

Dry forming of aluminium sheet metal: Influence of different types of forming tool microstructures on the coefficient of friction 18th

Dry forming of aluminium sheet metal: Influence of different...

引用

18th International ESAFORM Conference on Material forming, ESAFORM 2015

作者： Scholz, Peter Richard, Börner Kühn, Ralf Müller, Roland Schubert, Andreas Fraunhofer Institute for Machine Tools and Forming Technology Reichenhainer Str. 88 Chemnitz09126 Germany Technische Universität Chemnitz Reichenhainer Str. 70 09126 Germany

ISBN: (纸本)9783038354710

In the sheet metal forming industry lubricants are applied in forming processes to expand the technological boundaries by reducing friction and wear. The friction between tool and sheet metal is crucial to the deep drawing process. Due to economic and ecological reasons the aim of the manufacturers is to reduce or even avoid the use of lubricants. Consequently, this approach enables both a shortening of the process chains and an essential saving of resources. The advantages of structured forming tools in lubricated processes concerning the reduction of the coefficient of friction by the appearance of lubricating micro pockets are well-known. However, without using any lubricant this effect does not work. In this case the contact area is reduced by structuring the forming tool which affects the tribological system. In this paper the influence of microstructures with different geometries and surface treatments (uncoated / a-C: H: Si-coating) on the coefficient of friction in dry metal forming of the alloy AA5182 is compared to the frictional behaviour of unstructured forming tools using lubricant as reference. Before coating, the forming tools are machined by milling to generate tribologically effective microstructures. With the use of a strip drawing plant the effects of different surface microstructures and materials on the coefficient of friction are investigated. © (2015) Trans Tech Publications, Switzerland.

关键词： Lubricants

来源：评论

学校读者我要写书评

暂无评论

Investigation of tribological properties of AlMg4,5Mn0,7 in a warm forming process using the barrel compression test 18th

Investigation of tribological properties of AlMg4,5Mn0,7 in ...

引用

18th International ESAFORM Conference on Material forming, ESAFORM 2015

作者： Müller, Benedikt Jahn, Stephan F. Fang, Ru Schubert, Andreas Technische Universität Chemnitz Reichenhainer Str. 70 Chemnitz09107 Germany Fraunhofer Institute for Machine Tools and Forming Technology Reichenhainer Str. 88 Chemnitz09126 Germany

ISBN: (纸本)9783038354710

Within the German Collaborative Research Center 39 PT-PIESA the forming of micro cavities into aluminum sheets is one challenging task. During this forming process high forces and stresses occur which lead to a high tool wear. Hence, the actually applied cold forming process should be replaced by a warm forming process. This paper shows the tribological investigations for the warm forming process. Within the experiments the barrel compression test [1] is used to determine the friction conditions by varying the size of the cylindrically shaped samples of AlMg4,5Mn0,7, the forming degree and the lubrication condition (dry, graphite, forming oil). The flat punches were made from hardened steel 1.3343. The friction factor was calculated, and surface roughness was evaluated by 3D-laser microscopy. The experiments show that the friction factor increases, especially at forming degrees below 1 and for small specimen size, compared to cold forming processes [2]. In addition to that, an influence of the lubrication condition onto the surface roughness was observed. For experiments conducted with graphite, the surface roughness is significantly higher than for samples, which were formed dryly or with forming oil. © (2015) Trans Tech Publications, Switzerland.

关键词： Graphite

来源：评论

学校读者我要写书评

暂无评论

A Holistic Approach to Risk Oriented Lifecycle Engineering: Assessing Lifecycle Risks in Early Phases

引用

Procedia CIRP 2016年 48卷 265-270页

作者： Tobias Pickshaus Alexandra Kandt Stephan Hesse Karsten Fleischer Robert Schmitt Fraunhofer Institute of Production Technology IPT Steinbachstraße 17 52074 Aachen Germany Fachhochschule Südwestfalen Frauenstuhlweg 31 58644 Iserlohn Germany Laboratory for Machine Tools and Production Engineering WZL RWTH Aachen Steinbachstraße 19 52074 Aachen Germany

Innovative companies nowadays face demanding challenges as more complex product architectures and shorter product lifecycles endanger the success of innovative products. Rising product recalls and critical software patches are the observable consequences, threatening not only revenue but reputation and customer satisfaction. Therefore, it is evident that companies need to frontload their development processes while managing complexity through effective and in-depth product lifecycle monitoring. This becomes even more crucial in the context of multi-project management, employee turnover and low in-house production depth. In this paper, an approach to systematically assess project specific technical risks and uncertainties in early phases is presented. Based on qualitative ratings of risk and control factors and a staged aggregation and transformation of the assessment data into continuously updated maturity indicators, an effective method for product lifecycle monitoring is accomplished. It is shown how this will help companies to drastically reduce lifecycle costs. The approach is flanked by embedment into a real-time online information system satisfying several critical requirements. The application is validated by an industrial use case of an innovative manufacturer with a strong focus on critical uncertainties in subsequent product lifecycle phases.

关键词： Product Life Cycle Development Product Maturity Assessment Technical Risk Management Product Development Requirements Management

来源：评论

学校读者我要写书评

暂无评论

A New Model to Ascertain Product Maturity in Product Development Processes

引用

Procedia CIRP 2016年 50卷 173-178页

作者： Alexandra Kandt Tobias Pickshaus Karsten Fleischer Robert Schmitt Fachhochschule Suedwestfalen Haldener Straße 182 58095 Hagen Germany Fraunhofer Institute for Production Technology IPT Steinbachstraße 17 52074 Aachen Germany Laboratory for Machine Tools and Production Engineering WZL RWTH Aachen Steinbachstraße 19 52074 Aachen

Time, cost and quality are the three focused criteria in product development projects. While the factors time and costs can already be tracked very well during the entire course of a project through existing project management methods, the factor quality is by far more difficult to control. How mature the expected final product in the different development phases is, organizations seldom analyze systematically. Existing product maturity models and methods are mainly developed towards the needs and conditions of large companies within the automotive industry and therefore are found to be very complex and time-consuming to implement. This paper deals with the question to which extent existing quality methods are suited to monitor the product maturity during the development process of physical products. Based on established methods a new model is developed to calculate the product maturity during the development process with as less additional effort as possible. One characteristic value, which thereby highly influences the product maturity, is the uncertainty of the used decision data basis in terms of expert knowledge, technical simulation results or test results during the development process. The article ends with a practical validation of the new method, performed in an innovative, small and medium-sized company.

关键词： product development product maturity design validation maturity assessment

来源：评论

学校读者我要写书评

暂无评论

Optical micro-metrology of structured surfaces micro-machined by jet-ECM 15

Optical micro-metrology of structured surfaces micro-machine...

引用

15th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2015

作者： Quagliotti, Danilo Tosello, Guido Islam, Aminul M. Hansen, Hans N. Zeidler, Henning Martin, André Schubert, Andreas Brandao, Carla Riemer, Oltmann Technical University of Denmark Department of Manufacturing Engineering Kgs. Lyngby2800 Denmark Chemnitz University of Technology Faculty Mechanical Engineering Institute for Machine Tools and Production Processes Chemnitz09107 Germany Fraunhofer Institute for Machine Tools and Forming Technology IWU Chemnitz09126 Germany University of Bremen Laboratory for Precision Machining Bremen28359 Germany

ISBN: (纸本)9780956679079

A procedure for statistical analysis and uncertainty evaluation is presented with regards to measurements of step height and surface texture. Measurements have been performed with a focus-variation microscope over jet electrochemical micro-machined surfaces. Traceability has been achieved using as reference contact measurements from a calibrated stylus instrument. A statistical analysis has been carried out and the method of least squares has been implemented to correct for systematic behaviours. The combined uncertainty has been evaluated accordingly and the expanded uncertainty has been finally calculated as the confidence interval of 95 %. Results show that agreement within single digit micrometre (dimensional measurements) and tenths of micrometre (surface parameters measurements) can be achieved with the proposed methodology.

关键词： Least squares approximations

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：