检索结果-内蒙古大学图书馆

Author Correction: The influence of different sample preparation on mechanical properties of human iliotibial tract

Scientific reports 2021年第1期11卷 2673页

作者： Benjamin Fischer Sascha Kurz Andreas Höch Stefan Schleifenbaum ZESBO - Center for Research on the Musculoskeletal System Leipzig University Semmelweisstraße 14 04103 Leipzig Germany. Benjamin.fischer@zesbo.de. Department of Orthopedic Trauma and Plastic Surgery Spine Center Leipzig University Leipzig Germany. Benjamin.fischer@zesbo.de. ZESBO - Center for Research on the Musculoskeletal System Leipzig University Semmelweisstraße 14 04103 Leipzig Germany. Department of Orthopedic Trauma and Plastic Surgery Spine Center Leipzig University Leipzig Germany. Fraunhofer Institute for Machine Tools and Forming Technology Chemnitz Germany.

来源：评论

学校读者我要写书评

暂无评论

Different encapsulation strategies for implanted electronics

Different encapsulation strategies for implanted electronics

引用

作者： Winkler, Sebastian Edelmann, Jan Welsch, Christine Ruff, Roman Fraunhofer Institute for Machine Tools and Forming Technology Reichenhainer Straße 88 Chemnitz09126 Germany Fraunhofer Institute for Biomedical Engineering IBMT Ensheimer Strasse 48 66386 St. Ingbert Germany

Recent advancements in implant technology include increasing application of electronic systems in the human body. Hermetic encapsulation of electronic components is necessary, specific implant functions and body environments must be considered. Additional functions such as wireless communication systems require specialized technical solutions for the encapsulation. In this paper 3 different implant strategies based on the material groups silicone, ceramics and titanium alloys are evaluated. With the background of a specific application the requirements for the encapsulation are defined and include the implementation of electrical feedthroughs, wireless communication and wireless energy transfer as well as biomedical specifications such as hermetic sealing, mechanical stability and biocompatibility. The encapsulations are manufactured and qualified experimentally. © 2017 Sebastian Winkler et al., Published by De Gruyter.

关键词： Silicones

来源：评论

学校读者我要写书评

暂无评论

Hot forming of large spur gears

引用

Procedia Engineering 2017年 207卷 615-620页

作者： Dirk Landgrebe Andreas Sterzing Mike Lahl Matthias Milbrandt Anne Manuela Taubert Fraunhofer Institute for Machine Tools and Forming Technology Reichenhainer Straße 88 Chemnitz 09126 Germany

forming processes are generally characterized by a high degree of material utilization as well as short process times and, consequently, a decent economic efficiency. Considering their application in the manufacturing of large spur gears, forming processes offer a significantly attractive characteristic for the production of essential gearing components commonly used in wind turbines or marine engines. Furthermore, the hot forming process can be defined as an incremental forming process which enables the use of relatively low forming forces and results in a more compact design of the used machines. These conveniences are utilized in terms of roll forming with round tools to form gears and threads in a competitive way. Based on experiences gained over many years of researching rolling technologies, a cross-rolling process characterized by round tools with outer gearings was elaborated to realize a hot forming process for gear rolling of large spur gears at the fraunhofer IWU Chemnitz. Based on the already researched forming of smaller dimensioned gears, rolling trials utilizing a new hot-forming machinery - including defined inductive heating process before rolling - to realize large gears with outer diameters of up to 1000 millimeters were conducted. In terms of realizing this ambition, the derivation of the designated machine parameters for rolling large gears in real-life dimensions can be defined as a crucial factor. Consequently, the experimental research was followed by a mathematical analyzation of the forming forces, momenta as well as the necessary steps to determine the best possible scaling factors for the work pieces.

关键词： Hot forming gear rolling large gears bulk metal forming resource efficiency

来源：评论

学校读者我要写书评

暂无评论

Polypropylene based piezo ceramic compounds for micro injection molded sensors 21st

Polypropylene based piezo ceramic compounds for micro inject...

引用

21st Symposium on Composites, 2017

作者： Doerffel, Christoph Decker, Ricardo Heinrich, Michael Tröltzsch, Jürgen Spieler, Mirko Nendel, Wolfgang Kroll, Lothar Institute of Lightweight Structures Chemnitz University of Technology ChemnitzD-09107 Germany Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Straße 88 ChemnitzD-09126 Germany

ISBN: (纸本)9783035711981

Polymer matrix compounds based on piezo ceramic and electrically conducting particles within a thermoplastic matrix show distinctive piezoelectric and dielectric effects which can used for sensor applications. The electrical and mechanical properties can be adjusted in a wide range by varying the ratio of active filling particles and the matrix materials. The sensor effect of the compound is generated by the ceramic particles. A large ratio of piezo ceramic powder facilitates a high sensitivity. The electrical permittivity of the otherwise insulating matrix polymer can be adjusted by the amount of conductive filler. An aligned permittivity leads to a stronger electrical field in the ceramic particles. In contrast, too many conductive particles create a conductive network in the compound which short-circuits the sensors. The piezo ceramic compounds can be processed via micro injection molding for application as ceramic sensors. This offers a wide range of new sensor design variants, notably three-dimensional and highly complex geometries. However, there are two main demands for a highly sensitive sensor, which are conflicting. On the one hand the filler content of piezo ceramic particles in combination with electrical conductive carbon nanotubes must be very high;on the other hand the wall thickness should be as thin as possible. For filling cavities with a high aspect-ratio in an injection molding process, low viscosity polymer melts are necessary. These process characteristics conflict with the increasing viscosity by filling the melt with the particles. The sensor measuring area has to be designed as thin walled as possible. In order to overcome this obstacle a dynamically tempered mold design is applied to avoid solidification of the melt, before the mold is completely filled. The mold can be tempered by Peltier elements. The fully electric tempering is cleaner, more precise and more reliable than conventional water or oil tempering. © 2017 Trans Tech Publication

关键词： Molds

来源：评论

学校读者我要写书评

暂无评论

CAD-integrated modelling of Lattice structures for additive manufacturing and property evaluation of generated specimens

CAD-integrated modelling of Lattice structures for additive ...

引用

Materials Science and technology Conference and Exhibition 2017, MS and T 2017

作者： Kordass, R. Koch, P. Toeppel, T. Korn, H. Schoene, C. Mueller, B. Stelzer, R. Fraunhofer Institute for Machine Tools and Forming Technology IWU Noethnitzer Str. 44 Dresden01187 Germany Technical University of Dresden Institute of Machine Elements and Machine Design George-Baehr-Strasse 3c Dresden01069 Germany

ISBN: (纸本)9781510850583

Lattice structures are highly recommended as lightweight components. But until now, parts with lattice structures are mainly used for illustrative purposes. This is because their modelling, dimensioning, and build preparation still remains complex. To simplify this process a CAD-integrated tool is developed. Therein, lattice structures are represented on a parametric level. In the design process the topology of the whole structure as well as single lattice elements can be customized individually. It enables the designer to create fully adapted load carrying components and finally results in lightweight parts, less powder consumption, faster build time, and therefore lower costs during manufacturing. The mechanical properties of the structure are automatically computed by means of FEM. For verification of the mechanical property predictions, tensile tests are performed with Ti-6Al-4V and X3NiCoMoTi18-9-5 steel lattice structures following the design suggestions in draft standard DIN 50099. © Copyright 2017 MS&T17®.

关键词： Poisson ratio

来源：评论

学校读者我要写书评

暂无评论

Application of Substructure Techniques to Predict Cutting Stability for Mobile machine tools

引用

Procedia CIRP 2017年 58卷 110-115页

作者： Hendrik Rentzsch Martin Kolouch Matthias Putz Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Str. 88 09126 Chemnitz Germany

Mobile machining solutions use autonomous machining units that can be transported to different part locations, making possible easy maintenance and repair of large industrial equipment. Every new part and location results in different boundary conditions for the mobile machine tool-part system; influencing the dynamics of the combined system and necessitating different strategies for part/machine referencing and clamping. To facilitate efficient mutability and modularity in mobile machining solutions, this paper presents a dynamic substructuring strategy that combines the response characteristics of the mobile machine unit with different base models to obtain the synthesized mobile machine tool dynamic response. Numerical and experimental verification of the approach is provided. Framework presented can also combine measured response of parts for which models may not be available a priori. Methods presented provide experimental guidelines for establishing strategies for planning of machining strategies based on the evaluated dynamics.

关键词： Dynamics machine tool Chatter Substructuring

来源：评论

学校读者我要写书评

暂无评论

Process design for the shaping of sandwich sheets with sensor and actuator functionality

引用

Procedia Engineering 2017年 207卷 872-877页

作者： M. Nestler S. Hensel R. Müller W.-G. Drossel Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Str. 88 09126 Chemnitz Germany

Sandwich materials offer high stiffness in combination with small weight. Functional integration allows for additional active and passive functionalities. The paper deals with sandwich materials with sensor and actuator functionality using integrated piezoceramics. The challenges in production are examined in the paper by experiments and numerical simulation. In order to enable the sandwich material for forming, the adhesive properties are highly significant. An appropriate process chain is developed for manufacturing a semi-finished part with integrated piezoceramics which is suitable for forming.

关键词： deep-drawing finite element analysis layered structures Macro-Fibre-Composite process chain smart structures

来源：评论

学校读者我要写书评

暂无评论

Procedure Model for Efficient Simulation Studies which Consider the Flows of Materials and Energy Simultaneously

引用

Procedia CIRP 2017年 61卷 122-127页

作者： Johannes Stoldt Matthias Putz Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Straße 88 09126 Chemnitz Germany

The premise of this work is that more guidance is required for the application of the simultaneous simulation of material flows and energy flows. This assumption is supported by the findings of a systematic review which showed great diversity in earlier published case studies. Yet, other existing procedure models provide little advice regarding the manifestations of specific details of a simulation study. This paper presents a novel procedure model that is meant to increase the efficiency in simulation projects by providing detailed and consistent guidance for design choices in a simulation study. Selected results of its application are shown exemplarily.

关键词： Simulation Energy efficiency Decision making Procedure model Discrete event simulation

来源：评论

学校读者我要写书评

暂无评论

Automatic Adjustment of Car Body Fixtures Using Artificial Intelligence

引用

Procedia CIRP 2017年 62卷 600-605页

作者： R. Fritzsche A. Richter M. Putz Head of group assembly systems at Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Straße 88 Chemnitz 09126 Germany Scientific employee at Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Straße 88 Chemnitz 09126 Germany

In car-body production, the fixtures used for fixing the car-body panels during the joining pro-cesses predominantly consist of rigid constructions that require a time-consuming manual set-up process. To automate the adjustment process and reduce ramp up times, different adjustment modules have been developed at the fraunhofer IWU in order to meet specific requirements. Because of high quality requirements, produced components will be checked against an adjustment database. The exactly positioning for each clamping point will be derived, with the aid of mathematical algorithms and modern methods of artificial intelligence, based on measured values and the knowledge of the template technicians.

关键词： Quality management Body in white Ramp up Artificial intelligence Neuronal network Database

来源：评论

学校读者我要写书评

暂无评论

Evaluation of Shape Memory Alloy Bulk Actuators for Wear Compensation in Ball Screw Drives

引用

IFAC-PapersOnLine 2016年第21期49卷 88-94页

作者： Drossel, Welf-Guntram Junker, Tom Bucht, André y de Sosa, Iñaki Navarro Pagel, Kenny Fraunhofer Institute for Machine Tools and Forming Technology IWU Department Mechatronics Dresden01187 Germany Technische Universität Chemnitz Department of Machine Tools and Forming Technology Chemnitz09107 Germany

In this paper we present an approach to reset a preload loss in ball screw drives which enables to compensate losses of positioning accuracy due to wear over lifetime. The main purposes are reduced maintenance, longer service life and improved workpiece quality by regenerating the desired preload conditions which leads to a higher profit for manufacturers. For this purpose, a novel shape memory alloy (SMA) bulk actuator module for ball screw drives is designed. The device is developed to be implemented in standard drives without major changes in component design. It is installed between flanged nut and counter nut and replaces a spacer usually needed to set a defined preload. To achieve the required actuator performance SMA bulk actuators are investigated in detail. This covers their basic design and activation concepts. A prototype is designed and experimentally investigated; measurements show the proof of the concept. © 2016

关键词： Ball screws Drives machine tools Rigidity Shape memory effect Actuator modules Actuator performance Ball screw drives Basic designs Component design Positioning accuracy Shape memory alloys(SMA) Wear compensation

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：