Material Removal Rate and Tool Wear Ratio for Powder Mixed Dielectric Based Electric Discharge Machining

Electrical discharge machining (EDM) is used in die making and aerospace industries. This paper presents the performance study of the conventional EDM when used with powder mixed dielectric. Copper, graphite and mix (copper and graphite) were used. Pulse on, pulse off and current are the parameters which were varied at three levels. Copper, graphite and tungsten-copper were used as the electrode. The material removal rate and tool wear rate are assessed using design of experiments.

Optimization Multi Response on Electrical Discharge Machining Sinking Process Using Taguchi-Grey-Fuzzy Methods

Electronic Discharge Machining (EDM) sinking applied widely in advance material manufacturing, every process parameter will count on this company. Their performance evaluated by some parameters such as surface roughness and tool wear ratio. Then they will be a dependent variable on this research. Independent variables on this research are electrode polarization, gap voltage, duty factor and pulse current. Every variable has three levels, except electrode polarization has two levels. This research conducting using Taguchi matrix orthogonal L18 (21×33) methods. The aim of this experiment is to evaluate optimization parameter process on EDM sinking, using Taguchi-Grey-Fuzzy methods. Characteristics response optimal applied are ‘smaller better’ for surface response roughness and tool wear ratio. This research using DAC tool steel as work-piece. DAC is most widely used as die for aluminum and zinc die-casting. The aim of this research is finding contribution of variable in EDM sinking parameter. Result of this research show contribution from variable process to reduce variance total observed response simultaneously, in order are electrode polarization on 49,53%, gap voltage on 23,52%, duty factor on 5,45% and pulse current on 9,92%. From validated optimization in confirmation experiment, to conclude combination variable process optimal response value is electrode polarization on positive, gap voltage at 50V, duty factor at 0.5 and pulse current at 12A.

Arc characteristics in short electrical arc high-efficiency milling for GH4169

To solve core problems of slow arc response and unstable combustion, arc movement characteristics and arc action rules in short electrical arc milling are studied using a high-speed acquisition system and the Phantom high-speed camera in this article. To improve arc reignition, the characteristic parameters of arc discharge are determined as a discharge gap of 0.053 mm and discharge time of 2180 μs. A short electrical arc milling experiment with nickel-based superalloy GH4169 is carried out, confirming that the continuous stable discharge of the arc can easily produce a material removal rate of 40 g/min and a tool wear ratio of 0.8%. An SU8010 scanning electron microscope and energy spectrum analyzer are then used to study the erosion mechanism of GH4169 in short electrical arc milling. This article aims to expand the processing range of short electrical arc machining in the field of special material processing to provide experimental and theoretical bases for the development of short electrical arc milling technology theory and methods.

Study the Effects of Dielectric Type on the Machining Characteristics of γ-Ti Al in Electrical Discharge Machining

The current study surveys the results of using deionized water and kerosene as dielectrics in the machining outputs of γ-TiAl intermetallic compound obtained in electric discharge machining. Influences of these different dielectrics properties on machining speed, tool wear, surface cracks and roughness were compared. Scanning electron microscopy micrographs were prepared to investigate influences of dielectrics on the surface characteristics of electrically discharged samples. Results indicate which by kerosene dielectric; the material removal rate (MRR) is further compared to another one. But deionized water as dielectric causes higher tool wear ratio than kerosene dielectric. Electrical discharged samples in deionized water have higher surface roughness, in addition it contains surface cracks, whereas kerosene dielectric results better surface finish in low pulse current. According to XRD spectra electric discharge machining in deionized water and kerosene dielectrics produces Ti3 Al intermetallic compound on the produced surface.

An Influence of Parameters of Micro-electrical Discharge Machining on Wear of Tool Electrode

To achieve better precision of features generated using the micro-electrical discharge machining (micro-EDM), there is a necessity to minimize the wear of the tool electrode, because a change in the dimensions of the electrode is reflected directly or indirectly on the feature. This paper presents a novel modeling and analysis approach of the tool wear in micro-EDM using a systematic statistical method exemplifying the influences of capacitance, feed rate and voltage on the tool wear ratio. The association between tool wear ratio and the input factors is comprehended by using main effect plots, interaction effects and regression analysis. A maximum variation of four-fold in the tool wear ratio have been observed which indicated that the tool wear ratio varies significantly over the trials. As the capacitance increases from 1 to 10 nF, the increase in tool wear ratio is by 33%. An increase in voltage as well as capacitance would lead to an increase in the number of charged particles, the number of collisions among them, which further enhances the transfer of the proportion of heat energy to the tool surface. Furthermore, to model the tool wear phenomenon, a regression relationship between tool wear ratio and the process inputs has been developed.

A review on multiple responses process parameters optimization of turning Al-TiC[sub]p[/sub] metal matrix composites

Purpose: In this paper the Metal Matrix Composites of AL 7068 and TiC with differentproportions of (2%, 4%, 6%, 8%, and 10%) by using stir casting process, mechanicalproperties and machining responses are investigating.Design/methodology/approach: The samples are fabricated using stir casting, machiningof turning the samples by using Kilster Tool Lathe Dynamometer machining responses wereidentifying.Findings: In this research to find mechanical characterizations like flexural strength, Wearratio, impact strength, hardness, microstructure and also machining responses like surfaceroughness, cutting force, cutting power, tool wear ratio and can be optimized by multipleresponses.Research limitations/implications: This paper research about the mechanicalcharacterization and machining of AL-7068&TiC that focuses on machining responses andmicrostructures.Originality/value: By surveying the research articles the gap will be identified inAA-7068&TiC depended on machining responses and mechanical characterizations.

An Experimental Study of the Effects of Electrode Shapes on Micro-EDM Performances

In this paper, experiments were conducted to investigate the effects of cylindrical electrode and helical electrode on the micro electrical discharge machining (EDM) performances during micro-hole machining of titanium alloy. The results show that the material removal rate (MRR) and the tool wear rate (TWR) increase with open circuit voltage, regardless of electrode shapes. Compared to the cylindrical electrode, helical electrode can result in higher MRR and lower relative tool wear ratio (RTWR). It can be concluded that the helical electrode is more suitable than cylindrical electrode for machining micro parts.

Research on the Machining Performance of SiC/Al Composites Utilizing the BEAM Process

The Blasting Erosion Arc Machining (BEAM) process was applied to improve the machining efficiency of SiC/Al composites. A set of experiments were conducted on 20 vol% SiC/Al composites to find out the relationship between the parameters and machining performance. Results revealed that when the peak current was 500 A, the material removal rate (MRR) could be greater than 8,200 mm3/min and the tool wear ratio (TWR) was about 2%. Besides, the influence of polarity on the surface properties was also studied by using scanning electron microscope (SEM) and metalloscope. It disclosed that machining with a large peak current and a negative BEAM is suitable for bulk mass material removal, while the surface quality could be improved by applying the positive BEAM. Finally, a machined sample demonstrated the fesibility of BEAM for the machining of SiC/Al materials.

The Analysis of Processing Factors for Electro-Arc Machining

Electro-arc machining is similar with traditional electrical discharge machining (EDM) while the pulse duration of electro-arc machining is longer than that of EDM. The longer discharge was named arcing, and the arcing could lead to high material remove rate (MRR) and low tool wear ratio (TWR). Processing factors including discharge medium, tool polarity, tool material, voltage and rotational speed were chosen as input parameters on MRR and TWR. Taguchis method was used to evaluate their effects. All of the five processing factors had effects on MRR and TWR. The effects and the mechanism are also discussed.