The aim of this study is to establish general guidelines for minimizing the number of tests required to determine optimum process parameters in terms of formability for laser assisted single point incremental forming ...
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Grinding tool topography is one of the several key aspects of the modelling of a grinding process. Simplifying it could mean less processing time needed, but it can lead to inaccurate simulation results. Considering t...
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Grinding tool topography is one of the several key aspects of the modelling of a grinding process. Simplifying it could mean less processing time needed, but it can lead to inaccurate simulation results. Considering that, this research aims to develop a reliable method for NC-grinding processes with abrasive mounted points, describing the grinding tool surface using a single profile of kinematic cutting edges instead of its whole topography. In order to achieve this, numerical and empirical experiments were conducted proving the feasibility of the model to implement it for future simulations.
In contrast to common and classical joining technologies for composite/metal hybrid structures such as bonding and riveting, profile and contour joints offer a promising potential for novel lightweight hybrid structur...
In contrast to common and classical joining technologies for composite/metal hybrid structures such as bonding and riveting, profile and contour joints offer a promising potential for novel lightweight hybrid structures. First and foremost, joining systems with a form closure function enable to pass very high loads into rod- and tube-shaped fibre reinforced structures and achieve high degrees of material utilization for the composite part. This paper demonstrates the theoretical and technological principals for a resource efficient design and production of highly loaded thermoplastic composite profile structures with integrated metallic load introduction elements and a multi scale form closure. The hybrid structures are produced in an integral blow moulding process in which a braided tape-preform is simultaneously consolidated and formed into the metallic load introduction element. These metallic load introduction elements are manufactured in a two-stage process of external and internal hydroforming, after forming simulations have assured process stability for consistent quality.
To stay competitive and to fulfill the changing market needs, manufacturing companies have to adapt their manufacturing systems in frequent and short intervals. Hence, changeable and reconfigurable manufacturing syste...
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To stay competitive and to fulfill the changing market needs, manufacturing companies have to adapt their manufacturing systems in frequent and short intervals. Hence, changeable and reconfigurable manufacturing systems (RMS) are proposed and discussed in a multitude of research publications. While production planning becomes increasingly complex in this context, it has to be reliable and quick at the same time. Therefore, the performance and flexibility of manufacturing systems depends on actual and suitable planning data with high quality and wide range. In this context, a new approach for production planning in reconfigurable manufacturing systems is exposed in this paper. Data models, a configuration management and a sequential method for the resource planning help to integrate reconfigurable manufacturing systems’ key characteristics in production planning and control (PPC). Finally a prototypical application scenario, for the evaluation and demonstration of the feasibility of the planning approach, is outlined.
Temperature fields and subsequent heat flow into the components chip, tool and workpiece are of major significance for metal cutting. The temperature field in the tool influences for example the type of wear and the t...
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Temperature fields and subsequent heat flow into the components chip, tool and workpiece are of major significance for metal cutting. The temperature field in the tool influences for example the type of wear and the tool life and hence the temperatures evolving in the workpiece are responsible for later product quality. However, measurements of temperature fields in metal cutting require experimental efforts and are often prone to measurement errors. The present paper describes an analytical modelling method based on potential theory. Potential functions are successfully applied in other engineering fields, i.e. fluid mechanics and electrostatics. The fact that solutions for the same class of differential equation, namely the Laplace Differential Equation, are required give rise to apply the potential theory to describe the temperature field in metal cutting processes. While first approaches of the theory were more arbitrary, the so called panel method provides a systematic method for consideration of adiabatic boundaries and heat source strengths. In particular, cutting edge geometries and cutting edge radius as well as influence of wear can be considered with this method. Note that complex geometries and non-symmetrical heat sources cannot be covered by conventional analytical models of temperature fields in metal cutting. In terms of validation the modelling outcomes are compared to infrared camera pictures, conventional analytical model outcomes (modified model from Komanduri & Hou) and FEM simulation outcomes.
The rising requirements in cutting operations for higher performance and higher efficiency respecting also environmental phenomena are influencing the use of different coolants and flushing conditions. In machining di...
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The rising requirements in cutting operations for higher performance and higher efficiency respecting also environmental phenomena are influencing the use of different coolants and flushing conditions. In machining difficult-to-cut materials, in particular high-temperature materials, conventional emulsion cooling is unsuitable due to the insufficient cooling effect and the energy and cost intensive equipment required. For this reason new cooling and lubricating strategies have to be developed and investigated. Using hybrid processes, mainly by superposition of various cooling strategies, offers the potential to extend the existing technological process limits of conventional cutting processes. The paper introduces theoretical, experimental and simulation results with various innovative cooling strategies, such as high-pressure cooling, cryogenic cooling and aerosol dry lubrication in grooving, turning and drilling and derives the appropriate field of application for each flushing strategy.
Rising demand for energy caused by emerging economies, decreasing oil stocks, and the intended nuclear phase-out in some industrial countries has led to new problems concerning sufficient and on time energy supply. Si...
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The high-precision cutting of cemented carbide with geometrical defined cutting edge is due to high tool wear restricted. A new promising diamond based cutting material for machining cemented carbide has been develope...
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ISBN:
(纸本)9780956679079
The high-precision cutting of cemented carbide with geometrical defined cutting edge is due to high tool wear restricted. A new promising diamond based cutting material for machining cemented carbide has been developed by SUMITOMO ELECTRIC Hardmetal Corporation, Itami, Japan. In this paper, detailed information about the properties of the developed binderless-PCD are given. Furthermore, results of experimental studies with binderless-PCD as cutting material while milling cemented carbide are shown. As the result of this work the successful application of binderless-PCD as cutting material for machining cemented carbide could be shown. An arithmetical mean deviation Ra = 28 nm could be achieved by using a spindle speed n = 50 000 1/min and a feed per tooth ft = 0.5 μm.
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