检索结果-内蒙古大学图书馆

In-process evaluation of the grinding process using a new Barkhausen noise method

Procedia CIRP 2021年 99卷 202-207页

作者： Maximilian Rößler Matthias Putz Carsten Hochmuth Jens Gentzen Fraunhofer Institute for Machine Tools and Forming Technology Reichenhainer Strasse 88 09126 Chemnitz Germany

While the achievement of size and form tolerances is already state of the art for grinding, there are hardly any industrial solutions to identify thermo-mechanical process loads such as grinding burn. A system was developed, presented, and tested, which allows for the first time the in-process measurement of Barkhausen noise to indicate changes of the boundary zone’s state using a novel kind of sensor. The system enables tactile and non-contact measurement at sampling rates of up to 10 ms. During investigations on hardened shafts of 100Cr6, relevant influences on the in-process Barkhausen noise were identified and evaluated. Furthermore, cause-effect relationships between microstructural effects and the Barkhausen noise were detected.

关键词： Grinding In-process measurement Barkhausen noise

来源：评论

学校读者我要写书评

暂无评论

Towards the forming of concentrated Windings with trapezoidal Cross Sections for Increasing the Slot Filling Factor

Towards the Forming of concentrated Windings with trapezoida...

引用

International Electric Drives Production Conference (EDPC)

作者： Mirko Bach Maik Linnemann Markus Bergmann Verena Psyk Verena Kräusel Niclas Pohl Fraunhofer Institute for Machine Tools and Forming Technology Chemnitz Germany

ISBN: (纸本)9781665418102

The steadily growing use of industrial electric motors worldwide, combined with the need for improved efficiency, require advanced technologies that are beneficial with regard to resource efficiency and productivity. One possibility for saving raw materials is to reduce the size and weight of motors while maintaining the same performance. This can be achieved through an increase of the so-called slot filling factor, which has substantial influence on the torque generation in the electric machine. One way of increasing the slot filling factor is to shape the respective conductors in such a way that the cross sections correspond to their position. The focus of this paper lies on the description of interactions in the forming process of tooth coils with trapezoidal cross section geometry of the individual turns. In particular, the shaping of the coil heads of coils produced by sequential forming and subsequent bending is characterized via FEM forming simulation. Furthermore, the contribution presents a possibility for manufacturing coils of different geometries at high output rate by using flexible forming operations. Compared to manufacturing process chains suggested earlier, this approach allows considerable shortening and optimization of the process chain.

关键词： Coils Geometry Torque Shape Windings Wires Bending

来源：评论

学校读者我要写书评

暂无评论

Digital innovation hubs for robotics – TRINITY approach for distributing knowledge via modular use case demonstrations

引用

Procedia CIRP 2021年 97卷 45-50页

作者： Minna Lanz Jan Reimann Aleš Ude Niki Kousi Roel Pieters Morteza Dianatfar Sotiris Makris Tampere University Tampere Finland Fraunhofer Institute for Machine Tools and Forming Technology IWU Chemnitz Germany Jožef Stefan Institute Ljubljana Slovenia University of Patras Patras Greece

Robots are no longer stand-alone systems on the factory floor. The demand for industrial robots (market) is anticipated to be growing to 65 billion euros by the year 2023. Within all areas of robotics, the demand for collaborative and more flexible systems is rising as well. The level of desired collaboration and increased flexibility will only be reached if the systems are developed as a whole, e.g. perception, reasoning and physical manipulation. The rising need for collaborative robots in the automation industry is acting as a driver for this market and is expected to serve as a market opportunity for future growth. However, at the same time especially smaller companies have difficulties to formulate a concrete vision and strategies for the uptake of robotics, finding skilled workforce to develop and deploy the robot systems and/or work in the manufacturing industry. A number of Digital Innovation Hubs (DIHs) have been developed to enhance the knowledge and technology transfer from laboratories to factory floors, mitigating the skills gap and supporting the formulation of innovation ecosystems with the specific focus on small and medium-sized companies around Europe. The main aim of this paper is to introduce the concept and approach taken in H2020 TRINITY-project that aims to develop a Robotics Innovation Hub focused on Agile Production. The paper will introduce the concept and technical approach of the project, and discusses the preliminary results, challenges and opportunities of these kind of DIHs.

关键词： Digital innovation hub Modular Robotics ICT IIoT

来源：评论

学校读者我要写书评

暂无评论

Combined laser hardening and laser surface texturing forming tool 1.2379 11

Combined laser hardening and laser surface texturing forming...

引用

11th CIRP Conference on Photonic Technologies, LANE 2020

作者： Aragaw, Endalkachew Mekonnen Gärtner, Eric Schubert, Andreas Institute for Machine Tools and Production Processes Chemnitz University of Technology Reichenhainer Str. 70 09107 Germany Fraunhofer Inistitute for Machine tools and Forming Technology IWU Reichenhainer Str. 88 09126 Germany

This paper deals with the tribological performance of forming tool steel 1.2379. Laser hardening and Laser surface texturing are proposed as processes to improve this tribological performance. Hardening influences the surface hardness and wear resistance. While considering the parameter and the specific material, the correlation between heating power and material property is first modelled using FEM of the heat transfer. Based on the modelling result, the realization is performed by nanosecond laser and analyzed by SEM and by comparing the micro - hardness comparison with a reference value. Then textures are integrated into the hardened surface by picosecond laser ablation while focusing on its suitability for smooth dimples and on the examination by pin-on-disk tests for the effect of incorporating textures on the friction performance. Lower friction coefficients between tool and workpiece improve tool durability and product quality as well. © 2020 The Authors. Published by Elsevier B.V.

关键词： Microhardness

来源：评论

学校读者我要写书评

暂无评论

Developments in Powder Mixed EDM and its perspective Application for targeted Surface Modification

引用

Procedia CIRP 2022年 113卷 100-119页

作者： Andreas Schubert Viet D. Bui Ingo Schaarschmidt Thomas Berger André Martin Chemnitz University of Technology Professorship of Micromanufacturing Technology Reichenhainer Strasse 70 09107 Chemnitz Germany Fraunhofer Institute for Machine Tools and Forming Technology Reichenhainer Str. 88 09126 Chemnitz Germany

Although widely studied over the few decades, there are conflicting theories on the discharge mechanisms of powder mixed electrical discharge machining (PMEDM). Additionally, the dielectric flow plays a vital role in the distribution of powder particles in the machining gap, which significantly affects the powder deposition to the modified surface. In this paper, the literature on PMEDM surface modification is thoroughly reported. The conflicting mechanisms and the effects of PMEDM main machining conditions, such as powder and electrical parameters on improving mechanical and antibacterial properties as well as biocompatibility of the surface, have been discussed. To verify the separation mechanism of the discharge in PMEDM, single discharge investigations have been performed when silver nano-powder is mixed into the hydrocarbon-based dielectric fluid to modify Ti6Al4V surfaces. Surface topography, chemical composition as well as the deposited silver content and distribution over the crater surface when using positive and negative polarities are analyzed and discussed. Current waveforms of PMEDM and EDM without powder at varying discharge energies as well as with and without ultrasonic vibration assistance are recorded and analyzed. For the transfer of fundamental results to a perspective application, CFD simulation is used to calculate the flow field of the dielectric fluid and analyze the velocity and distribution of the nano-powder within the working gap of a setup with internal flushing. The results show that PMEDM is a potential technology for machining medical devices with simultaneous antibacterial surface modification.

关键词： Powder mixed EDM Surface modification Single discharge CFD simulation Antibacterial

来源：评论

学校读者我要写书评

暂无评论

Hybrid approach to evaluate surface integrity based on grinding power and Barkhausen noise 6th

Hybrid approach to evaluate surface integrity based on grind...

引用

6th CIRP Conference on Surface Integrity, CSI 2022

作者： Heinzel, Jonas Jedamski, Rahel Rößler, Maximilian Karpuschewski, Bernhard Epp, Jérémy Dix, Martin Mapex Center For Materials And Processes University Of Bremen Bibliothekstr. 1 Bremen28359 Germany Leibniz Institute For Materials Engineering Iwt Badgasteiner Str. 3 Bremen28359 Germany Fraunhofer Institute For Machine Tools And Forming Technology Reichenhainer Straße 88 Chemnitz09126 Germany

In this paper the potential of a reliable characterization of surface and subsurface properties is presented by measurement of process forces for determining the specific grinding power Pc and the micromagnetic Barkhausen noise in cylindrical grinding trials. Therefore different dressing conditions by grinding with conventional wheel with varying process parameters are investigated. It is shown that an identified lower thermal limit in a Pc-t-diagram (contact time t) to prevent tempering zones in the ground surface and subsurface area of case hardened steel is applicable even if the condition of the grinding wheel is intentionally influenced by dressing. Finally a soft sensor concept for the use of the specific grinding power and in perspective also the use of the Barkhausen noise for process control is derived. © 2022 The Authors.

关键词： Grinding (machining)

来源：评论

学校读者我要写书评

暂无评论

Usage-based leasing of complex manufacturing systems: A method to transform current ownership-based into pay-per-use business models

引用

Procedia CIRP 2022年 107卷 1238-1244页

作者： Mohaned Alaluss Chris Drechsler Robin Kurth Anton Mauersberger Steffen Ihlenfeldt Michael Marré Rainer Labs Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Strafβ 88 09126 Chemnitz Germany Institute of Mechatronic Engineering Technische Universität Dresden Helmholtzstr. 7a 01069 Dresden Germany South Westphalia University of Applied Sciences Frauenstuhlweg 31 58644 Iserlohn Germany

Manufacturing technology with its cost- and resource-intensive manufacturing machines like machine tools, whose amortization often takes several years, is characterized by a high degree of individualization. Here, the need for increasingly complex as well as individualized products leads to the demand for high flexibility and resilience in complex manufacturing systems. The increasing uncertainty and volatility in the markets pose high economic risks for machine operators with ownership-based business models to enter new technologies. Consequently, this restrains the innovative and creative power of manufacturing companies. Although leasing models exist in various industry sectors like printing industry or compressed air supply, their implementation is still challenging due to the high degree of complexity regarding machine system, process, and services of the leasing product. In this paper, a novel method, with increased consideration of technical-technological aspects, to transform current ownership-based into usage-based business models like pay-per-use, is proposed. The resulting method also considers the pay-per-use readiness through an initial assessment of the existing manufacturing system.

关键词： perfomance-based contracting pay-per-use method business models manufacturing machines machine tools industry 4.0 agile production

来源：评论

学校读者我要写书评

暂无评论

machine learning for material characterization with an application for predicting mechanical properties

引用

GAMM Mitteilungen 2021年第1期44卷 e202100003-e202100003页

作者： Stoll, Anke Benner, Peter Data-Mining and Machine Learning Fraunhofer Institute for Machine Tools and Forming Technology IWU Chemnitz Germany Computational Methods in Systems and Control Theory The Max Planck Institute for Dynamics of Complex Technical Systems Magdeburg Germany

Currently, the growth of material data from experiments and simulations is expanding beyond processable amounts. This makes the development of new data-driven methods for the discovery of patterns among multiple lengthscales and time-scales and structure-property relationships essential. These data-driven approaches show enormous promise within materials science. The following review covers machine learning (ML) applications for metallic material characterization. Many parameters associated with the processing and the structure of materials affect the properties and the performance of manufactured components. Thus, this study is an attempt to investigate the usefulness of ML methods for material property prediction. Material characteristics such as strength, toughness, hardness, brittleness, or ductility are relevant to categorize a material or component according to their quality. In industry, material tests like tensile tests, compression tests, or creep tests are often time consuming and expensive to perform. Therefore, the application of ML approaches is considered helpful for an easier generation of material property information. This study also gives an application of ML methods on small punch test (SPT) data for the determination of the property ultimate tensile strength for various materials. A strong correlation between SPT data and tensile test data was found which ultimately allows to replace more costly tests by simple and fast tests in combination with ML. © 2021 The Authors. GAMM - Mitteilungen published by Wiley-VCH GmbH.

关键词： machine learning

来源：评论

学校读者我要写书评

暂无评论

Local Microscopic and Integral Macroscopic Analysis of Magnetic Pulse Welds and Deformations for Dissimilar Metal Joints 13th

Local Microscopic and Integral Macroscopic Analysis of Magne...

引用

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

作者： Huberth, Frank Ragupathi, Balaji Scheffler, Christian Psyk, Verena Preußner, Johannes Fraunhofer Institute for Mechanics of Materials IWM Woehlerstrasse 11 Freiburg79108 Germany Department of Sustainable Systems Engineering EFM University of Freiburg Faculty of Engineering Emmy-Noether-Str. 2 Solar Info Center 4 Freiburg79110 Germany Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Strasse 88 Chemnitz09126 Germany

ISBN: (纸本)9783030753801

Magnetic pulse technology is used for high-speed forming as well as for joining. Joining by magnetic pulse welding (MPW) is the combination of high-speed forming, impact, and a resulting weld in the collision zone of the accelerated flyer and the impacted target. This MPW process allows the welding of dissimilar metals, like aluminum and steel for lightweight construction or aluminum and copper for E-mobility applications. Investigations showed up scattering in binding strength and failure for comparable welds. The effects leading to the bond formation and the reasons for the quality variation are not fully understood until now. For further understanding, a combined experimental investigation of integral and local mechanical weld properties supported by simulations and microstructure analysis was performed considering dissimilar metal joints of aluminum EN AW1050 H14/24 and copper Cu DHP R240 for different configurations and impact energies. Lap shear tests served for quantifying integral mechanical properties, while local mechanical properties were determined by microtensile tests on samples prepared in the thickness direction of the welded metal sheets and microstructural analysis. These local microscopic testing and analysis results provide information about the weld strength distribution. These investigations give new hints on the bond-forming mechanisms and local process depending on material effects. © 2021, The Minerals, Metals & Materials Society.

关键词： Welds

来源：评论

学校读者我要写书评

暂无评论

VariPath: A Database for Modelling the Variance of Human Pathways in Manual and HRC Processes with Heavy-Duty Robots

VariPath: A Database for Modelling the Variance of Human Pat...

引用

IEEE International Conference on Robotics and Automation (ICRA)

作者： Mohamad Bdiwi Ann-Kathrin Harsch Paul Reindel Matthias Putz Fraunhofer Institute for Machine Tools and Forming Technology IWU Chemnitz

ISBN: (数字)9781728173955

ISBN: (纸本)9781728173962

Unlike robots, humans do not have constant movements. Their pathways are individually changeable and influenced by circumstances. This paper presents a method to investigate human pathway variations in a real study. In systematically selected tasks, human pathways are examined for 100 participants in manual and human-robot collaboration (HRC) scenarios. As a result, the variations of pathways are presented depending on various features: e.g. in nearly all cases the variance of women's walking pathways is smaller than that of men. VariPath database can be used in any planning process of manual or HRC scenarios to ensure safety and efficiency.

关键词： Legged locomotion Service robots Task analysis Planning Atmospheric measurements Particle measurements

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：