Analýza opotřebení EDM elektrod v rozích a na hranách

The analysis of EDM electrodes wear in corners and edges

journal article in Web of Science

en

Die-sinking electrical discharge machining is an unconventional technology that allows to machine all at least minimally electrically conductive materials regardless of their physical and mechanical properties. Despite the fact that it is not a conventional technology, the tool gets also worn out, which is a tool electrode. The wear of the electrode does not only mean its loss but also the degradation of the shapes that are transferred to the resulting workpiece. For this reason, a design of experiments was conducted with 6 input factors, 2 were categorical: the electrode material (copper, graphite) and workpiece material (steel 1.2363 and steel 1.2343ESR) and 4 were numerical: Open-voltage, Pulse current, Pulse on-time and Pulse off-time. In the framework of this design of experiments, the wear of the used graphite and copper electrodes at their corners and edges was evaluated, which was made possible by the use of electron microscopy and the use of approximation circles. Furthermore, the eroding speed, the topography of the machined samples and the morphology of the surfaces of the used electrodes were investigated. It has been recognized that the use of a graphite electrode will allow for more accurate workpiece shapes and less wear.

Elektroerozivní obrábění je nekonvenční technologie, která je umožňuje obrábět všechny alespoň minimálně elektricky vodivé materiály bez ohledu na jejich fyzikální a mechanické vlastnosti. I přes to, že se nejedná o konvenční technologii i zde dochází k opotřebení nástroje, kterým je nástrojová elektroda. Opotřebení elektrody neznamená pouze její úbytek ale také degradaci tvarů, které jsou přenášeny na výsledný obrobek. Z toho důvodu byl proveden plánovaný experiment s 6 vstupními faktory, 2 byly kategoriální: materiál elektrody (měď, grafit) a materiál obrobku (ocel 1.2363 a ocel 1.2343ESR) a 4 byly numerické: Open-voltage, Pulse current, Pulse on-time a Pulse off-time. V rámci tohoto plánovaného experimentu bylo vyhodnocováno především opotřebení použitých grafitových a měděných elektrod v jejich rozích a na hranách, což bylo umožněno užitím elektronové mikroskopie a použití aproximačních kružnic. Dále byla zkoumána rychlost erodování, topografie obrobených vzorků i morfologie povrchů použitých elektrod. Bylo dosaženo poznání, že použití grafitové elektrody umožní výrobu přesnějších tvarů obrobků a také dochází k jejich menšímu opotřebení.

Die-sinking electrical discharge machining is an unconventional technology that allows to machine all at least minimally electrically conductive materials regardless of their physical and mechanical properties. Despite the fact that it is not a conventional technology, the tool gets also worn out, which is a tool electrode. The wear of the electrode does not only mean its loss but also the degradation of the shapes that are transferred to the resulting workpiece. For this reason, a design of experiments was conducted with 6 input factors, 2 were categorical: the electrode material (copper, graphite) and workpiece material (steel 1.2363 and steel 1.2343ESR) and 4 were numerical: Open-voltage, Pulse current, Pulse on-time and Pulse off-time. In the framework of this design of experiments, the wear of the used graphite and copper electrodes at their corners and edges was evaluated, which was made possible by the use of electron microscopy and the use of approximation circles. Furthermore, the eroding speed, the topography of the machined samples and the morphology of the surfaces of the used electrodes were investigated. It has been recognized that the use of a graphite electrode will allow for more accurate workpiece shapes and less wear.

EDM; elektroeroyivní obrábění; opotřebení; plánovaný experiment; elektrody; rohy

EDM; electrical discharge machining; wear; design of experiment; electrode; corners

05.10.2020

Springer Nature

Polská republika

1644-9665

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