Elektro erozyon ile işlemede işleme mekanizmasının ısıl modellenmesi

Bu çalışmada, elektro erozyon ile işlemede işparçası malzemesinin aşınmasının sonlu elemanlar yöntemi ilemodellemesi yapılmıştır. Isıl-elektriksel model, tek bir boşalım için geliştirilmiştir. Geliştirilen model dielektriksıvı içerisinde elektriksel boşalım sonucu oluşan enerjiyi, plazma kanalı genişliğini ve ortamda meydana gelenısı transferlerini içermektedir. Literatürde yer alan deneysel çalışma parametreleri kullanılarak, plazma kanalındaoluşan enerjinin işparçası malzemesinde oluşturduğu sıcaklık dağılımı incelenmiştir. Ergime sıcaklığının üstüneçıkan işparçası malzemesinin ergime kraterinden kaldırıldığı kabul edilmiştir. Çalışmada, sonlu elemanlaryöntemini kullanarak analiz yapan ANSYS Workbench v.11 programı kullanılmıştır. Elektro erozyon ile işlemetekniği zamana bağlı ısıl analiz yöntemi kullanılarak simüle edilmiştir. Farklı işleme parametrelerinde eldeedilen teorik sonuçların deneysel sonuçlarla büyük ölçüde örtüştüğü görülmüştür.

Thermal modelling of machining mechanism in electrical discharge machining

In this study, theoretical model of workpiece material removal in electrical discharge machining (EDM) wasdeveloped. Thermo-electrical model was developed for a single discharge. Developed model includes severalaspects like, generated energy formed by the electrical discharge in liquid media, plasma channel radius variationand heat transfer from the channel. By using different experimental study parameters used in literature, effect ofgenerated energy in plasma channel on workpiece was investigated. The developed model evaluates thetemperature distribution in the workpiece material using finite element solver ANSYS Workbench (v.11)software. It’s assumed that the workpiece material reaches the melting point of workpiece material was removedfrom the surface. Electrical discharge process was simulated by using transient thermal analysis. Finally, thedeveloped model has been validated by comparing the theoretical material removal results with the experimentalones.

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