Influence of duty factor on the die-sinking Electrical Discharge Machining of high-strength aluminum alloy under rough machining

Abstract

The use of high-strength aluminium alloys as material for injection molding tools to produce small and medium batches of plastic products as well as prototyping molds is becoming of increasing demand by the tooling industry. These alloys are replacing the traditional use of steel in the cases above because they offer many advantages such as very high thermal conductivity associated with good corrosion and wear resistance presenting good machinability in milling and electrical discharge machining operations. Unfortunately there is little technological knowledge on the Electrical Discharge Machining (EDM) of high-strength aluminium alloys, especially about the AMP 8000 alloy. The duty factor, which means the ratio between pulse duration and pulse cycle time exerts an important role on the performance of EDM. This work has carried out an experimental study on the variation of the duty factor in order to analyze its influence on material removal rate and volumetric relative wear under roughing conditions of EDM process. The results showed that high values of duty factor are possible to be applied without bringing instability into the EDM process and with improvement of material removal rate and volumetric relative wear

Optimizing electric discharge machining parameters for tungsten-carbide utilizing thermo-mathematical modelling

“…where P is energy intensity (5) Using these equations it is possible to find the effect of the magnitude of the area of the heat source upon depth of depression (crater). The knowledge of the heat source area is necessary in order to verify the theoretical derivations and the neglect of this area would lead to great errors.…”

Aspects on the optimization of die-sinking EDM of tungsten carbide-cobalt

“…Considering the aforementioned EDM phenomenon, an asymmetric material removal of the electrode and the workpiece can be achieved by the appropriate choice of electrical parameters, electrode polarity, type of working gap flushing, planetary movement of the electrode and thermophysical properties of electrode/workpiece materials. According to Amorim & Weingaertner (2002), another EDM variable strictly associated to the electrical parameters and that influences on the machining characteristics is the duty factor τ, illustrated in Fig. 1.…”

Electric Discharge Machining Method for various Metal Matrix Composite Materials

“…Aspect ratio is defined as the length / diameter for any shape of electrode and it becomes thickness/ diameter for rotating disc electrode. Singh et al [35] investigate in their experiment that shape of the electrode affect the TWR i.e. lowers the aspect ratio higher the TWR.…”