An Examination on Improving WEDM and Vacuum Brazing Process Failure of PCD Tool

Abstract

Background/Objectives: It aims to improve the tool lifespan by improving defects in WEDM(Wire Electric Discharge Machining) and vacuum brazing process, which are PCD(Polycrystalline Diamond) tool making process.

Methods/Statistical analysis: When machining a PCD disk plate by WEDM processing the elution of the binder on the PCD surface by the electrolyte is measurement by a tool microscope and compared. In addition, when the PCD tip and base material are bonded by the vacuum brazing process, the deflective strength of biding section is measurement.

Findings: PCD disk plate was processed by WEDM machining, it was compared that the binder of the PCD surface was eluted according to the level of exposure to the electrolyte. When the PCD disk plate was precipitation of the electrolyte for about 10 minutes, about 70% of the binder eluted. However, when the SM45C plate was attached to the PCD surface, of binder an elution was drastically lowered. The deflective strength of the joints with temperature was measured in vacuum brazing, which is the binding process between PCD tip and base material. When vacuum brazing was applied by a temperature pattern with a maximum temperature rise a 690? the deflective strength of the joint between the PCD and the material was measured to be 430[N/mm2].

Improvements/Applications:The level of elution of the binder was determined according to the time of exposure of the PCD surface to the electrolyte. In addition, it was confirmed that the bonding strength was improved by the melting temperature condition of the filler metal for vacuum brazing.It may be applied to manufacturing processes of various rotating tools like end mill, drill cutting tool, etc.