Now showing 1 - 6 of 6
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Mikrofräswerkzeuge mit Schneiden aus cBN

2018 , Uhlmann, E. , Polte, J. , Polte, M. , Kuche, Y. , Wiesner, H.

Die Mikrozerspanung ist eine Kerntechnologie bei der Fertigung von Mikrospritzgussformen. Die hohen Ansprüche an die geometrische Genauigkeit und Oberflächenrauheit erfordern den Einsatz hochfester Werkstoffe. Jedoch unterliegen aktuelle Fräswerkzeuge bei der Mikrozerspanung einem hohen Verschleiß. Einen Lösungsansatz bietet der erfolgreich in der Makrozerspanung eingesetzte Schneidstoff kubisch-kristallinesBornitrid(cBN). Ziel der Untersuchungen war es daher, detaillierte Informationen zur Bearbeitung von gehärtetem Stahl mit cBN-Mikrofräswerkzeugen bereitstellen zu können.

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Automatisierte Qualitätskontrolle

2015 , Uhlmann, E. , Oberschmidt, D. , Löwenstein, A. , Kuche, Y. , Wiemann, S.

Inhalt eines Forschungsprojektes der Firma OTEC Präzisionsfinish GmbH und des Fraunhofer-Instituts für Produktionsanlagen und Konstruktionstechnik IPK ist die Entwicklung eines Maschinenprototypen zur Feinbearbeitung mit automatisierter Qualitätskontrolle durch integrierte optische Messtechnik und Messsoftware. Im Rahmen des durch das Zentrale Innovationsprogramm Mittelstand (ZIM) vom Bundesministerium für Wirtschaft und Energie (BMWi) geförderten Projektes wurde dazu eine kompakte, für die Automatisierung und Integration von Messtechnik ausgelegte Maschine entwickelt. Mithilfe dieser Maschine können Werkstücke, wie etwa Nockenwellen oder Zerspanwerkzeuge, mit dem Verfahren Tauchgleitläppen bearbeitet und definierte Kantenradien erzeugt sowie in einem automatisierten Prozess gemessen werden. This paper presents a machine prototype for the finishing of edges and surfaces of work pieces. The prototype has an integrated optical measurement device, which can be used for the control of the process results and possibly automated remachining. The machine is used for the preparation of milling tools. Process parameters and their effects are analyzed and an approach for the automated setting of the process parameters is shown.

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Influence of cutting edge preparation on the performance of micro milling tools

2016 , Uhlmann, E. , Oberschmidt, D. , Löwenstein, A. , Kuche, Y.

A main reason for premature tool failure in micro milling is the irregular wear behavior of the cutting tools. An approach to improve the tool wear behavior is a defined cutting edge preparation using immersed tumbling. A particular challenge is the cutting edge preparation of micro milling tools with small diameters D ⤠0.5 mm. High loads within the preparation process can lead to outbreaks of the cutting edge and tool breakage. Furthermore, the influence of changed cutting edge geometry regarding the process behavior has to be more examined for these tool diameters. In this paper, micro milling tools with a diameter D = 0.2 mm will be prepared and the influence on the cutting process will be presented and discussed. The experiments will show a better wear behavior for the prepared tools and an improved surface roughness on the machined workpiece.

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Verfahren zur automatisierten Reinigung

2014 , Uhlmann, E. , Oberschmidt, D. , Kuche, Y.

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Effects of different cutting edge preparation methods on micro milling performance

2016 , Uhlmann, E. , Oberschmidt, D. , Kuche, Y. , Löwenstein, A. , Winker, I.

In micro milling, which is mostly used in mold and die making, process reliability and predictability of tool failure are important. Particularly in precision and micro machining, tool breakage is hardly detectable and the requirements on accuracy are very high. Immersed tumbling is an appropriate process for the defined cutting edge preparation of micro milling tools. Its effects like increasing tool wear performance and tool life has been evaluated. In this paper, different cutting edge preparation processes showed that in cutting tests different effects occur regarding tool wear, process forces and surface quality. Immersed tumbling leads to the lowest active force Fa, but magnet finishing leads still do a slightly better surface quality.

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Cutting edge preparation of micro milling tools

2014 , Uhlmann, E. , Oberschmidt, D. , Kuche, Y. , Löwenstein, A.

Micro milling is commonly used industrially for the production of precision components. Premature tool wear is usually the reason for a short tool life of cemented carbide end mills. An approach to improve the tool wear behavior is the defined cutting edge preparation. In this contribution, experimental investigations on the formation of cutting edge geometry during immersed tumbling of micro milling tools are presented and discussed. It could be shown that it is possible to prepare end mills with a diameter D = 1 mm and to generate edge radii of 4.0 m r 31.2 m. Investigations about the correlations between the cutting edge geometry and the tool wear behavior in micro milling operations showed decreased flank and crater wear as a result of an appropriate cutting edge preparation.