Entwicklung des Qualitätsmanagements in Forschung und Lehre

In this paper we discuss the development of the research focused on quality management at the Department of Economics and Business Management (WBW), University of Leoben. In parallel to the development of quality management in business, we set out the milestones in teaching and professional training as well as the implementation of the quality management system according to the trend of New Public Management at the WBW. After outlining current topics in postgraduate training, we highlight new possible research directions for quality management.     

Modellbildung und Simulation von Klimawechselprüfungen

For many years the number and complexity of laboratory tests used in the automotive industry has been increasing steadily in order to simulate field-specific climatic corrosion loads and the corrosion damage resulting from them. The test environment defines the environmental impact applied to the component globally by specifying control variables to be set in the test. However, the initiation of a damage mechanism is essentially influenced by the retroactive effect of the design on local, transient load characteristics, such as different wetting intervals and local media composition. In order to better evaluate the multitude of available tests with regard to corrosive damage, the knowledge of local corrosive loads is essential, but these cannot be measured with either spatial or time resolution. This gap can be closed by using numerical simulation.Concepts and basics of a multiscale CFD simulation model as a basis for virtual corrosion testing are presented, which show that numerical simulation can make a significant contribution to understanding complex corrosion tests and the effects of product design. In addition to the test-typical test sequences, the simulation also takes into account the type of media loading and flow control in the chamber, the geometry of the test specimens, and the thermal properties of the material. The advantages of numerical simulation for the support and optimization of climate testing are illustrated with an exemplary comparison of a climate change test in the model and experiment.     

Mechanisches und chemisches Verhalten von Lean-Duplex-Stählen nach Wärmebehandlungen in kritischen Temperaturbereichen

Lean-duplex steels represent a low-cost option compared to austenitic and standard-duplex steels. This is achieved by reducing the content of nickel and molybdenum through substitution with manganese and nitrogen, respectively. These elements also improve the mechanical properties. In this work, two lean-duplex steels X2CrMn- NiN22–5-2 (LDX 2101) and X2CrNiN23–4 (SAF 2304) are compared with respect to their mechanical und chemical behaviour after different annealing conditions at 475 °C and 700 °C. All visible differences are the consequence of phase separation (α'-phase), precipitations (σ-phase, carbides and nitrides) as well as the formation of secondary austenite.     

Beiträge des WBW zur Entwicklung der Logistik in Forschung und Lehre

On the occasion of the 50th anniversary, the contributions of the Department of Economic and Management Sciences (WBW), University of Leoben, to the development of logistics in research and education are highlighted. After a discussion of the milestones of logistics and related dissertations of the department WBW, the newly resulting curriculum is presented. The paper concludes with an outlook on a possible new research topic.     

Erholungs- und Rekristallisationsverhalten von technisch reinem Molybdän

While initially technically pure molybdenum was applied mainly because of its high temperature properties, in recent years it found new applications also at room temperature. An important example is sputtering targets required for manufacturing of TFT-LCDs (Thin Film Transistor-Liquid Crystal Displays). In view of the increasing dimensions of the glass substrate to be coated, new demands are placed on the production. The significant increase in dimensions and the requirements on the purity of the materials demand new investigations of the recovery and recrystallization behavior of molybdenum since recrystallization diagrams have been published back in the 1960ies. In addition, advanced procedures using the scanning electron microscope (e.g. ECCI-Electron Channelling Contrast Imaging) permit a more detailed differentiation between deformed, recovered and recrystallized grains. Of interest is especially the characterization of the grain's substructure in view of the high stacking fault energy of the body-centred cubic molybdenum leading to an increased tendency of recovery. The present study was aimed at the determination of a recrystallization diagram for technically pure molybdenum of the high quality presently achieved, to be discussed in comparison with the diagram published by Pink in 1965.     

Klärung des spezifischen Korrosionsverhaltens von mikroporigen Chromüberzugssystemen in CaCl<Subscript>2</Subscript>-Elektrolyten

To describe the so-called Russian-mud corrosion of microporous chromium plating systems on decorative car parts, the corrosion behavior of this plating system has been studied in concentrated aqueous Calcium chloride electrolytes. Scanning electron microscopy (SEM) and energy dispersive x?ray spectroscopy (EDX) have been used to characterize the specific corrosion mechanism of corrosive stressed chromium plating systems from Russia. Potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) have been performed to evaluate the electrochemical corrosion behavior of each plating. Two different corrosion mechanisms can be identified to describe the corrosive attack, the dissolving of the chromium plating, and the undercutting of the chromium plating.     

Praxis und Wissen – Aus der Industrie – Neues von der Montanuniversität – Mitteilungen des BVÖ – Personalnachrichten – Tagungsankündigungen

BHM Verbandsnachrichten

Praxis und Wissen – Aus der Industrie – Neues von der Montanuniversit?t – Mitteilungen des BV? – Personalnachrichten – Tagungsankündigungen     

Identifikation von Verbesserungsmöglichkeiten des Förderbetriebes von Tagebauen mit Hilfe von Simulations- und Planungstechniken

Truck haulage is applied in many open pit operations and usually accounts for a significant ratio of total costs. The paper presents several measurement and analysis approaches applicable to regular operations to identify eventual potentials for improvements. For better illustration some data of such an exercise from the iron ore mine of VA Erzberg are given, which is the largest mining operation in Austria. For an expedient analysis the importance of a clear distinction between availability, utilization and technical efficiency is underlined. Discussed data analysis covers path geometry, overall cycle times, truck motion tracing and qualitative aspects. For prediction purposes the analysis must be extended on a simulation level. Prediction quality is significantly improved if the model is scaled and validated by measured results. Once established such a model can be particular helpful for mid- and long-term planning tasks, such as evaluating proposed geometric or organizational changes of hauling, or to assess the development of performance and costs in the future.     

Praxis und Wissen – Aus der Industrie – Neues von der Montanuniversität – Mitteilungen des Bergmännischen Verbandes Österreichs – Tagungsankündigungen – Hinweise auf Neuerscheinungen

BHM Verbandsnachrichten

Praxis und Wissen – Aus der Industrie – Neues von der Montanuniversit?t – Mitteilungen des Bergm?nnischen Verbandes ?sterreichs – Tagungsankündigungen – Hinweise auf Neuerscheinungen     

Vergleich des Abbrandverhaltens beim Rezyklieren von Aluminiumsp?nen und -briketts

At the processing of aluminium castings 3?C5 % swarf is arising. The fine material is transferred into the secondary aluminium metallurgy cycle. The melting process can be performed by using salt. Due to the high reactivity of the swarf, it is important that it has no contact to the surface. At the non-salt process different pumping systems can be used, but most of the companies do not have such devices. When the fine particles are charged directly on to the surface of the bath the losses of aluminium can be higher than 70 %. One possibility to avoid such enormous causalities is to briquette the fine material. In this paper the melting loss of aluminium swarf and briquettes is compared. Some practical trials have been done in a batch process with an induction furnace. In cooperation with the ATM Recyclingsystems GmbH some investigations concerning the behaviour of the aluminium swarf and briquettes at the melting process will be done.     

Charakterisierung bainitischer Gefügezustände in Schmiedestählen

Recent steel developments for highly dynamic loaded closed die-forgings illustrate a trend towards fine grained microstructures, which are formed directly by the forging temperature and which do not need any further heat treatment. Experiments are performed using three MnB-steel grades with different silicon contents. In order to estimate the thermodynamic data and transformation diagrams and to define reasonable test parameters, the software JMatPro is used. The isothermal transformation behavior at different temperature levels in the bainitic region is dilatometric determined using a Gleeble 3800 testing machine. The results provide a first overview on the formation of a fine microstructure and the expected mechanical properties. At transformation temperatures just above the M_s-temperature, strength values of almost 1000 MPa could be achieved, i.e. significant improved fatigue endurance can be expected. Due to the fine microstructure, excellent Charpy-V-toughness values are found.     

Zur Frage der Belastung und Stabilität von Bergfesten im Hartgesteinsbergbau am Beispiel des „Post-Pillar“-Abbauverfahrens

In “post-pillar” mining a regular system of rooms and pillars is developed in the lowest horizon of the mineral deposit. In ascending slices the deposit is mined using backfill to support the pillars and to serve as a working platform. The system is exceptionally flexible, making it possible to follow the irregularities of the mineral deposit and to achieve high extraction rates. Because of this flexibility in horizontal and vertical directions mining dimensions change regularly. This, however, has numerous effects on pillar loading and pillar stability. Two loading cases have to be distinguished, namely displacement and load controlled systems. In the first case the lateral extent of the extraction area and the height of extraction are critical parameters as they determine the convergence in the stoping area and the stiffness of pillar. In the second case the height of loosening zone above the extraction area which can develop in the advanced stages of stoping is critical. Stiffness of the mining system reduces with lateral extent of extraction area but increases with height of extraction area because of changed overall geometry of stoping area. In contrast pillar stiffness decreases with mining height. The combined effects of these changes are that pillar load increases with lateral extent of extraction area but decreases with total extraction height. Height of zone of loosened rock above extraction area increases with width and height of extraction area. With proper rock mechanics planning and careful consideration of complex interaction of parameters the “post-pillar” mining method can be a save and economic method for extraction of irregularly shaped mineral bodies. There are still a number of open questions concerning the influence of backfill on behaviour of slender support pillars.     

Potentiale und Herausforderungen neuer Vermessungstechnologien im Bergbau – Der Einsatz unbemannter Flugkörper zur Erfassung von Geodaten

Mine surveying is an important part of mining science and technology. It includes all measurements, calculations and mapping which serve the purpose of ascertaining and documenting geospatial information at all stages from prospecting to exploitation and utilizing mineral deposits. Using unmanned aerial vehicles (UAVs) in conjunction with automated multi-view processing pipelines offers new ways for aerial data acquisition to perform surveying tasks in a more flexible, faster, cheaper and safer way. In this paper the potential of unmanned aircraft in the mineral resource industry is shown, especially in the light of accuracy, UAV-surveying is compared to conventional methods and disadvantages are discussed.