Fügen von Aluminium- und Kohlenstofffaserstrukturen*/Joining of aluminium and carbon fibre structures - An innovative joining technology based on semi-solid forming strategies

2017 ◽  
Vol 107 (10) ◽  
pp. 743-747
Author(s):  
M. Prof. Liewald ◽  
L. Marx
Keyword(s):  
Carbon Fibre ◽  
Metal Forming ◽  
Carbon Fabric ◽  
Forming Technology ◽  
Joining Technology ◽  
Aluminium Sheets ◽  
Semi Solid ◽  
The University ◽  
The Impact

Das Institut für Umformtechnik (IFU) an der Universität Stuttgart befasst sich derzeit mit der Entwicklung eines neuartigen Verfahrens zum formschlüssigen Fügen von Aluminium- und Carbonstrukturen. Zwei Aluminiumbleche werden dabei lokal auf ein Temperaturniveau knapp oberhalb ihrer Solidustemperatur erwärmt, sodass ein dazwischenliegendes Carbongewebe durch die dann teilflüssige Aluminiummatrix infiltriert werden kann. Dieser Fachartikel befasst sich mit dem Einfluss wichtiger Prozessparameter.   The Institute for Metal Forming Technology (IFU) of the University of Stuttgart aims at the development of a novel joining method for combining aluminium and carbon fibre structures. Two aluminium sheets with carbon fabric in between are conductively heated by two electrodes up to semi-solid state, so the woven carbon fabric is infiltrated with aluminium. This paper focuses on the impact of different process and sample parameters on the quality of the joint.

Joining of carbon fibres with aluminium structures – Processing and infiltration modelling

2020 ◽  
Vol 54 (25) ◽  
pp. 3767-3775
Author(s):  
Lukas Marx ◽  
Mathias Liewald
Keyword(s):  
Metal Forming ◽  
Lightweight Design ◽  
Solid Material ◽  
Carbon Fibres ◽  
Carbon Fabric ◽  
Infiltration Process ◽  
Forming Technology ◽  
Material State ◽  
Aluminium Sheets ◽  
Semi Solid

Against the background of today's lightweight design, an innovative joining technique has been developed at the Institute for Metal Forming Technology/Stuttgart for combining aluminium sheet structures with carbon fabrics. During the process of Joining of Carbon Fibres with Aluminium Structures (JOCA process), two or more aluminium sheets with carbon fabric layers in-between are initially conductively heated up into the semi-solid material state by means of two adjacent electrodes of a welding gun. If heated up to a liquid share of 30% to 60%, the aluminium matrix infiltrates the carbon fabric resulting into a firm joint after solidification of the metal material. This publication provides an overview of the research results obtained by experimental and numerical investigations of the infiltration process achieved so far.

Production of Titanium Alloy Components by Semi-Solid Forming

2012 ◽  
Vol 192-193 ◽  
pp. 515-520 ◽  
Author(s):  
Levente Kertesz ◽  
Mathias Liewald
Keyword(s):  
Mechanical Properties ◽  
Metal Forming ◽  
Medical Engineering ◽  
High Variability ◽  
Development Work ◽  
Forming Process ◽  
Forming Technology ◽  
Semi Solid ◽  
New Research ◽  
The University

The relatively high costs of processing titanium alloys and the high variability in the products' quality currently represent the major economic obstacles to using such materials in either production or medical engineering. For this reason, new research and development work at the Institute for Metal Forming Technology of the University of Stuttgart is pursuing the objective of improving and enhancing pre-existing processes for these types of materials. In doing this, aspects are considered which specify definite mechanical properties during and after the forming process as well as reduce the costs by means of cutting the manufacturing times, increase the use of semi-finished products and minimise finishing operations.

Zmiana modelu zarządzania i nadzoru nad jakością kształcenia w szkolnictwie wyższym. Perspektywa doświadczeń Republiki Federalnej Niemiec

2020 ◽  
pp. 137-149
Author(s):  
Krzysztof Szewior
Keyword(s):  
Quality Of Education ◽  
Research Approach ◽  
University Management ◽  
Strategic Partner ◽  
Higher Education Reforms ◽  
The University ◽  
The Impact ◽  
Desk Research

The author focuses on the manner and effects of German higher education reforms that have changed the model of university management. The point of reference is the quality of education and its role, how universities ensure it, and how it is verified through evaluation and accreditation. These elements divide the article into two parts: a part about quality and a part about evaluation and accreditation. The analysis includes the impact of global processes and Europeanization. The research approach is characteristic for public policies, sciences of management and quality. The theories used in this article: the theory of systems and neo-institutionalism, as well as perspectives: the university as an active strategic partner, entrepreneurial university, the third role of universities. The publication is based on desk research and on the analysis of processes.

Bending Strength and Fracture Behaviour of Metal-Ceramic Interpenetrating Phase Composites Manufactured by Using Semi-Solid Forming Technology

2022 ◽  
Vol 327 ◽  
pp. 111-116
Author(s):  
Laura Schomer ◽  
Kim Rouven Riedmüller ◽  
Mathias Liewald
Keyword(s):  
Bending Strength ◽  
Fracture Behaviour ◽  
Structural Characteristics ◽  
Process Window ◽  
Metallic Material ◽  
Forming Technology ◽  
Metal Ceramic ◽  
Semi Solid ◽  
The Impact ◽  
Interpenetrating Phase Composites

Interpenetrating Phase Composites (IPC) belong to a special category of composite materials, offering great potential in terms of material properties due to the continuous volume structure of both composite components. While manufacturing of metal-ceramic IPC via existing casting and infiltration processes leads to structural deficits, semi-solid forming represents a promising technology for producing IPC components without such defects. Thereby, a solid open pore body made of ceramic is infiltrated with a metallic material in the semi-solid state. Good structural characteristics of the microstructure as the integrity of the open-pore bodies after infiltration and an almost none residual porosity within the composites have already been proven for this manufacturing route within a certain process window. On this basis, the following paper focuses on the mechanical properties such as bending strength of metal-ceramic IPC produced by using semi-solid forming technology. Thereby, the impact of the significant process parameters on these properties is analysed within a suitable process window. Furthermore, a fractographic analysis is carried out by observing and interpreting the fracture behaviour during these tests and the fracture surface thereafter.

Scientific journal in the educational space of the university

2021 ◽  
pp. 137-145
Author(s):  
Akhurbek А. Magometov ◽  
Boris A. Takhokhov
Keyword(s):  
Scientific Journal ◽  
Scientific Publication ◽  
Educational Process ◽  
Teaching Staff ◽  
Perspective View ◽  
Research Activities ◽  
The University ◽  
The Impact

The article presents the authors ‘view on the activities of the scientific journal” Bulletin of the North Ossetian State University named after K. L. Khetagurov”. The relevance of the article is due to a significant increase in the role of research work of teachers and students of universities and the requirements for their publication activity; the importance for the university of having highly rated scientific journals and the increasing importance of the scientific publication of the university for improving the training of students. At the scientific and theoretical level, the changes that were determined by the modernization of education in the country and the need to improve the quality of scientific publications in accordance with the vector of development of international high-ranking publications and the desire of the university management and the editorial board to keep the journal in the trend of modern science are understood. Attention is paid to the problem of evaluating and reviewing scientific articles, the idea of the impact of reviews on the development of scientific knowledge is justified; the systematic work of the editorial board on the introduction of scientific research into the educational process of the university is shown. The new tasks of the editorial board are considered, the solution of which will contribute to improving the quality of the publication and the research activities of the teaching staff and students of the university. The purpose of the work is to substantiate the author’s approach to the current state, functioning and perspective view of the development of the university scientific publication and to determine its place in the modern scientific and educational space. The research methodology is based on systematic, activity-based and culturological approaches using such methods as systematization, generalization, analysis, description and comparison.

scholarly journals SQoF-WEAR Project. The Use of Wearable Devices to Identify the Impact of Stress on Workers’ Quality of Life

2021 ◽  
Vol 7 (1) ◽  
pp. 25
Author(s):  
Patricia Concheiro-Moscoso ◽  
Betania Groba ◽  
Sílvia Monteiro-Fonseca ◽  
Nereida Canosa ◽  
Cristina Queirós
Keyword(s):  
Quality Of Life ◽  
Public Health Problem ◽  
Wearable Devices ◽  
Assessment Tools ◽  
Self Report ◽  
Major Public Health Problem ◽  
The University ◽  
And Control ◽  
The Impact

(1) Background: Stress is a major public health problem due to its relevant health, social and economic repercussions. Moreover, stress can be associated with work; when stress increases over time, burnout can occur, an occupational phenomenon recognized by the WHO in 2019. There is interest in the use of wearable devices to monitor and control stressors and their influence on the condition of workers. This study aims to identify the level of job stress and its influence on the quality of life of workers. (2) Methods:This longitudinal study was carried out between the end of May and mid-July 2021. Three assessment tools along with a daily and a weekly questionnaire were computerized through the RedCap platform. The participants had to fill out the diary and weekly questionnaires and wear a Xiaomi Mi Band 5 during the project. (3) Results and discussion: Thirty-six workers from the University of Coruña and from the University of Porto participated in the project. This study promotes the awareness of workers regarding their work stress and the influence of this factor on their quality of life using physiological (e.g., activity, sleep, and heart rate) and psychological indicators (self-report questionnaires in different moments).

scholarly journals Antecedents of organizational identification: implications for employee performance

2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Syeda Wajiha Kazmi ◽  
Syeda Tuba Javaid
Keyword(s):  
Employee Engagement ◽  
Organizational Identification ◽  
Employee Performance ◽  
Quality Of Education ◽  
Content Type ◽  
Perceived Supervisor Support ◽  
The University ◽  
The Impact ◽  
The Relationship

Purpose This study aims to investigate the impact of three determinants of organizational identification (OID) on employee performance (EP) in the context of private business institutions. Design/methodology/approach A sample of 175 permanent faculty members from four top universities in Karachi, Pakistan, was interviewed using a five-point Likert scale questionnaire. The data were inserted in SPSS 22 and SmartPLS v 3.2 for performing the analysis. Findings Results of the study showed a significant effect in perceived supervisor support on OID; OID; job satisfaction and EP; and mediating relationship. Conversely, an insignificant effect was observed in workplace incivility. Research limitations/implications It is highly recommended that organizations work on the areas that lead to enhancing their employees’ performance. Also, human resource should create a healthy culture that promotes initiatives, open-door policies and discourages power distance. Lastly, one of the key responsibilities of management is to strengthen their OID because employees are more likely to identify with their supervisors if they invest in the organizations they work for. Practical implications This study will help strengthen the relationship between supervisors and university employees. It will guide the supervisors to acknowledge and appreciate the efforts of their subordinates and develop recreational policies and employee engagement activities. In addition, it will help develop a conducive environment and enhance the quality of education in the university and the society. Originality/value Understanding the determinants of OID on EP in the educational context is very important as it enhances the quality of EP and the overall quality of education of the institution.

Fließpressen hohler Wellen mit Wanddickenvariation/Cold forging of hollow shafts with wall thickness variation – Numerical investigation of a hollow forward extrusion process with adjustable deformation zone

2020 ◽  
Vol 110 (10) ◽  
pp. 684-688
Author(s):  
Alexander Weiß ◽  
Mathias Liewald
Keyword(s):  
Numerical Investigation ◽  
Metal Forming ◽  
Extrusion Process ◽  
Cold Forging ◽  
Thickness Variation ◽  
Part Geometry ◽  
Forming Technology ◽  
Wall Thickness Variation ◽  
The University ◽  
Hollow Shafts

Die Fertigung von Hohlwellen mit komplexer Innengeometrie bedingte bisher meist aufwendige Prozessrouten. Ein am Institut für Umformtechnik der Universität Stuttgart entwickeltes Kaltfließpressverfahren soll nun die wirtschaftliche und flexible Fertigung von Hohlwellen mit Wanddickenvariation ermöglichen. In diesem Beitrag werden das Verfahren beschrieben und die Ergebnisse der numerischen Untersuchung des Einflusses der Werkzeugkinematik auf die erzielbare Pressteilgeometrie dargelegt.   Usually, the production of hollow shafts with complex internal geometry by cold forging requires extensive process routes. A novel cold forging process developed at the Institute for Metal Forming Technology at the University of Stuttgart allows for an economical and flexible production of hollow shafts. This article describes the manufacturing process and presents the results of a numerical investigation for determining the influence of tool kinematics on the achievable part geometry.

Modelling of Fine Blanking Process of the Aluminium Sheets

2011 ◽  
Vol 473 ◽  
pp. 290-297 ◽  
Author(s):  
Wojciech Wieckowski ◽  
Piotr Lacki ◽  
Janina Adamus
Keyword(s):  
Dimensional Accuracy ◽  
Soft Materials ◽  
Fine Blanking ◽  
Technological Quality ◽  
Aluminium Sheets ◽  
The Impact ◽  
Blanking Process ◽  
Cut Surface ◽  
Stress And Strain Distribution

The required technological quality of the blanked products can be achieved through operations of fine blanking. This allows for obtaining products with improved dimensional accuracy and good quality cut-surface. In order to cut products from soft materials, including aluminium and its alloys, the methods of fine blanking with upsetting and fine blanking with reduced clearance are typically employed. The study presents the results of numerical modelling of the fine blanking process for a disk made of 1-millimetre sheet aluminium EN AW-1070A. The goal of the numerical simulations was to evaluate the effect of clearance between blanking die and the punch, and the impact of V-ring indenter on stress and strain distribution in the shearing zone.

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