Fraunhofer-Institut für Produktionsanlagen und Konstruktionstechnik IPK

Filters

5
Reset filters

Settings
Now showing 1 - 5 of 5
  • Publication
    Modeling of the wet immersed tumbling process with the Discrete Element Method (DEM)
    ( 2021)
    Uhlmann, Eckart
    ;
    Fürstenau, J.-P.
    ;
    Kuche, Yves
    ;
    Yabroudi, Sami
    ;
    Polte, Julian
    ;
    Polte, Mitchel
    Immersed tumbling is an industrially established process for finishing of components made of metal, ceramic or plastic. In this process, the components are completely surrounded by a wet, abrasive medium, which allows burrs to be removed and surfaces to be polished. In order to gain specific insights into the influence and flow properties of the abrasive media used in this process, numerical approaches using the Discrete Element Method (DEM) with the Rocky DEM software are presented within these investigations. A complete process simulation could be realised by means of a digital machine tool. The immersed tumbling process with cone-shaped polymer abrasive media is implemented by use of a liquid bridge model. The results were validated by experiments with an industrially used immersed tumbling machine tool and for the first time allow sound statements about the contact conditions and interactions of the abrasive media with the workpiece.
  • Publication
    Influence of the fatty acid profile on the lubricating film formation in micro-milling process on 7050-T7451 aluminum alloy
    ( 2020)
    Chanes de Souza, Milena
    ;
    Wiesner, Hagen Maximilian
    ;
    Kuche, Yves
    ;
    Polte, Julian
    ;
    De Oliveira Gomes Júnior, Jefferson
    ;
    Uhlmann, Eckart
    This work studies the technical performance of vegetable-based metalworking fluids as a more environment-friendly alternative for micro-milling on 7050-T7451 aluminum alloy. Micro-milling investigations were performed using two vegetable-based oils, two emulsions prepared with the same vegetable-based oil and a commercial emulsion for comparison. It was noted that the vegetable-based oils with high oleic fatty acid profile provide better lubrication films than mid-oleic fatty acid profiles. However, the wear of the cutting tools is slightly more pronounced when the high oleic oil was used. When these oils were used for the preparation of vegetable-based emulsions, the high oleic emulsion presents better lubricating potential and provides high surface quality than the mid-oleic emulsion. However, the wear of the cutting tool was similar. The vegetable-based metalworking fluids showed similar performance than the commercial reference. Therefore, the oil with high oleic fatty acid profiles presents good technical performance and can be used in vegetable-based metalworking fluids formulations.
  • Publication
    Influence of cutting edge micro-geometry in micro-milling of copper alloys with reduced lead content
    ( 2018)
    Uhlmann, Eckart
    ;
    Kuche, Yves
    ;
    Polte, Julian
    ;
    Polte, Mitchel
    Especially copper-zinc alloys (CuZn) with good machining properties are used for electrical components and fittings. By using copper alloys with lead content of 1 % < Pb < 3 % an improved chip breakage can be achieved. Legal regulations require the reduction of lead and demand further knowledge about the effect of the material properties in interaction with the used micro-milling tools. In this contribution the cutting conditions of copper as well as four copper alloys were examined. The results show considerable differences in the resultant surface roughness and burr formation. Furthermore, the influence of two different tool geometries and variied cutting edge micro-geometries were investigated while machining CuZn21Si3P. Thereby, tools with increased cutting edge radii rv showed increased active forces Fa, burr height h0 and decreased surface roughness.
  • Publication
    PKD-Glattdrückwerkzeuge für den Werkzeug- und Formenbau
    ( 2018)
    Uhlmann, Eckart
    ;
    Polte, Mitchel
    ;
    Polte, Julian
    ;
    Guhde, Sebastian
    ;
    Kuche, Yves
    ;
    Kappel, Thomas
    Es wurden Glattdrückwerkzeuge mit Sphärenkopf aus polykristallinem Diamant der Firma Baublies AG, Rennigen, genutzt. Das Werkzeugkonzept orientiert sich dabei an den aktuellen Herausforderungen beim Werkzeug- und Formenbau sowie an handelsüblichen Zerspanwerkzeugen. In diesem Beitrag sind das Werkzeugkonzept, der Versuchsaufbau und die ersten Ergebnisse zur Kraftmessung dargestellt. Darüber hinaus werden die erreichbare Härtekennwerte und die Rauheitskennwerte in Abhängigkeit verschiedener Prozessparameter sowie zu den Ausgangswerten verglichen.
  • Publication
    Verschleißverhalten neuartiger Mikrofräswerkzeuge mit Schneiden aus CBN bei der Hartzerspanung
    ( 2018)
    Uhlmann, Eckart
    ;
    Polte, Julian
    ;
    Polte, Mitchel
    ;
    Kuche, Yves
    ;
    Wiesner, Hagen Maximilian
    In der Mikroproduktionstechnik bei der Zerspanung mit geometrisch bestimmter Schneide und Werkzeugdurchmessern von D < 1mm stellt der Werkzeugverschleiß einen entscheidenden Faktor für die Entstehung hoher Fertigungskosten dar. Ein großes Anwendungsfeld der Mikrozerspanung ist die Fertigung hochpräziser Spritzgusswerkzeuge für die Serienfertigung von Präzisionskunststoffteilen. Gefordert werden dabei hohe geometrische Genauigkeiten und niedrige Oberflächenrauheitskennwerte. Um diese Anforderungen zu erfüllen, ist eine stetige Forschungsarbeit notwendig. Ein Ansatzpunkt zur Optimierung der Fertigungsprozesse ist der Einsatz neuartiger Schneidstoffe und Werkzeuggeometrien.