Fraunhofer-Institut für Produktionsanlagen und Konstruktionstechnik IPK

Filters
Reset filters

Settings
Now showing 1 - 3 of 3
  • Publication
    Maschine und Technologie für die Bahnerosion mit gasförmigem Dielektrikum zur Herstellung von Mikrostrukturen
    (Fraunhofer Verlag, 2022)
    Perfilov, Ivan
    Im Rahmen der vorliegenden Arbeit erfolgt die Entwicklung eines neuartigen Maschinenkonzepts für die Bahnerosion mit gasförmigem Dielektrikum. Die Maschine verfügt über einen für die Trockenfunkenerosion entwickelten IsoPuls-Relaxationsgenerator, welcher die Variabilität und Steuerbarkeit eines statischen Generators mit der hohen Entladefrequenz sowie geringen Entladeenergien von Relaxationsgeneratoren kombiniert, sowie auch über eine technologisch optimierte Maschinensteuerung. Die technologischen Untersuchungen und erzielten Erosionsergebnisse zeigen die Eignung des vorgestellten Maschinenkonzepts sowie das Anwendungspotenzial der Bahnerosion mit gasförmigem Dielektrikum für den Einsatz in der Mikroproduktion. Damit liefert diese Arbeit nicht nur einen Beitrag zum besseren Prozessverständnis der Trockenfunkenerosion, sondern zeigt auch eine Vorgehensweise auf, wie ein innovatives Maschinenkonzept und die zugrunde liegende Technologie zu realisieren sind.
  • Publication
    Helical electrodes for improved flushing conditions in drilling EDM of MAR-M247
    ( 2018)
    Uhlmann, Eckart
    ;
    Perfilov, Ivan
    ;
    Yabroudi, S.
    ;
    Schweitzer, Luiz
    ;
    Polte, Mitchel
    The machining of precision holes in difficult to machine materials or alloys with high aspect ratios Ï and under consideration of the cost-effectiveness of the overall process is still a challenge. Electro-discharge machining (EDM) is predestined for such purposes. Flushing is one key factor for the precise machining of bore holes with high aspect ratios Ï. Nevertheless, the capabilities of the flushing conditions are often underrated regarding an improved process stability, an increased material removal rate VW, a decreased machining time tero, as well as the tool wear ÎIE. Therefore, the present investigation considers the influence of an outer geometry of cylindrical rod tool electrodes to improve the electro-discharge drilling process. Different electrodes made of brass, with helical flutes along the shank, are compared with the basic geometry, a cylindrical rod electrode, with respect to their flushing capabilities. All electrodes have an outside diameter d = 3 mm. It is suggested that the machining process will stabilise and the material removal rate VW will increase due to improved removal efficiency of erosion particles (debris). Through holes with a total depth h = 16 mm have been machined by use of Design of Experiments (DoE) approved process parameters in nickel based superalloy MAR-M247. By use of a helical shaped electrode the machining time tero was reduced by 39 % compared to the cylindrical rod electrode.
  • Publication
    Electro-discharge drilling with MP-based carbon fibre electrodes
    ( 2018)
    Uhlmann, Eckart
    ;
    Perfilov, Ivan
    ;
    Yabroudi, S.
    ;
    Schweitzer, Luiz
    ;
    Polte, Mitchel
    For the electro-discharge drilling of micro-holes with small diameters D the production and the guidance of the tool electrode are most challenging. For holes with diameters D ⤠50 μm the required electrodes have to be produced by electro-discharge dressing, which leads to a considerable increase in the production effort as well as the production costs. The small diameters 5 μm ⤠d ⤠15 μm as well as the good electrical conductivity κ of carbon fibres make it possible to use a single carbon fibre as an electrode for electro-discharge drilling. The paper presents the results of experiments with non-rotating single carbon fibres as tool electrodes for electro-discharge drilling. The process parameters were optimised for the machining of through-holes in a workpiece made of stainless steel 1.4310 with a thickness h = 20 μm and h = 50 μm respectively.