Erosion Rate, Surface Finish and Electrode Wear in Electric Discharge Machining(EDM) of Dental Alloys

摘要

A precise fit of dental restorations is critical in all aspects of prostheticdentistry. Fabrication of a prosthesis with a high degree of accuracy is difficult due to the dimensional changes of different dental materials. EDM is an extremely accurate non-contact machining process with a precision as small as 0.002 mm. The objectives of this study were to investigate how changes in amperage and on-time of the EDM process affect the metal removal rate (MRR) and surface finish (Ra) of representative dental materials. The percentage of electrode wear (PEW) of representative electrode materials in different metal-electrode combinations was also studied. Three representative dental metals (workpieces) were used; Type III gold (Ney), Olympia ceramo-metal Alloy (Jelenko) and titanium (Ti) (Rematitan). Type III gold and ceramometal alloy were cast in bars 6mm square and 30 mm in length. Ti ingots were used as provided by manufacturer.