EFFECT OF POWDER MIXED DIELECTRIC ON MACHINING PERFORMANCE IN ELECTRIC DISCHARGE MACHINING (EDM)

Abstract

ABSTRACT

In this study, the variations of machining performance outputs, namely, workpiece surface roughness, workpiece removal rate, electrode wear rate, relative wear, workpiece surface hardness, and workpiece surface microstructure were experimentally investigated with the varying machining parameters for metal powder mixed dielectric liquid in electrical discharge machining (EDM). The machining tests were conducted by using prismatic steel workpiece and copper electrodes with graphite and boric acid powders (H3BO3) mixed kerosene dielectric at different powder concentrations and pulse time settings. The experiments have shown that the type and concentration of the powders mixed into the dielectric and the pulse time were effective on machining performance outputs in EDM.

 

 

 

Keywords

• Key Words: electric discharge machining, powder mixed dielectric, surface roughness, machining rate, electrode wear, surface hardness, micro structure

ELEKTRO EROZYON İLE İŞLEMEDE TOZ KARIŞIMLI DİELEKTRİĞİN PERFORMANS ÜZERİNE ETKİLERİ

Abstract

Bu çalışmada, elektro erozyon ile işlemede (EEİ) metal tozu karışımlı dielektrik sıvı kullanımında işparçası yüzey pürüzlülüğü, işparçası işleme hızı, elektrot aşınma hızı, bağıl aşınma, işparçası yüzey sertliği ve mikroyapısı gibi performans çıktılarının işleme parametreleri ile gösterdiği değişim deneysel olarak incelenmiştir. Bu amaçla prizmatik çelik işparçası, prizmatik bakır elektrot, borik asit (H3BO) ve grafit tozları katılmış gazyağı dielektrik kullanılarak değişik toz konsantrasyonları ve vurum süreleri için işleme deneyleri yapılmıştır. Yapılan deneyler, vurum süresinin ve dielektrik sıvıya karıştırılan tozların ve konsantrasyonlarının EEİ yönteminin performans çıktıları üzerinde etkili olduğu göstermiştir

Keywords

• elektro erozyon ile işleme, toz karışımlı dielektrik sıvı, yüzey pürüzlülüğü, işleme hızı, elektrot aşınması, yüzey sertliği, mikro yapı

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