In the industrial field, electric discharge machining (EDM) is the most commonly used non-traditional machining process because it has the potential to machine electrically conductive materials of high hardness. To satisfy the need for rapid and economical fabrication of EDM electrodes, techniques that use the addition of more metal in the manufacturing process are gaining in popularity. This study presents an investigation of the characterization of ternary metals (Cu–Ni–TiN) for EDM electrodes by using powder metallurgy, which leads to enhancement of the mechanical properties, such as the hardness, electrical properties, and other properties, for the formation of Cu in Ni-TiN electrodes using a cold press at pressures of 18, 20, and 22 MPa. The influences of the parameters of this process were identified for the betterment of Cu–Ni–TiN on the surface. The specimens were calcined in a furnace at 1100 °C for 1 h, with a mixture of argon and hydrogen gas as a controlled gas in the ratio of 95:5. The specimens were investigated in terms of hardness, electric resistivity, apparent density, and porosity. The results show that the 80% Cu–3% Ni–17% TiN electrode at 18 MPa had the highest hardness (124.38 HV) and the lowest electric resistivity (0.39188 cm), while the specimen increased Cu with a ratio of 85% Cu–3% Ni–12% TiN, and a pressure of 20 MPa was found to have the highest density (8.5472 g/cm3) and the lowest porosity (6.2922%). As a further confirmation of the above results, the X-ray diffraction (XRD) patterns of the surfaces of the specimens exhibited major phases that supported the ternary Cu–Ni–TiN phase. However, we also achieved the successful use of Cu–Ni–TiN electrodes as a titanium source (as an alternative to the conventional metal powder) to provide a novel approach to fabricating composite electrodes through the EDM process.

No abstract

The aim of this research was to study the feasibility for applications related to powder metallurgy in EDM electrode fabrication by combination of the percentage Cu-C-Ni element. The experiment was performed by comparing preliminary distribution results of particle size before and after the grinding of metal powders. The work-piece was pressed at a pressure of 200 Psi using a uniaxial press machine. The pressed green compact work-piece was then baked in a furnace. The gas inside the furnace that was used to control the temperature during the cold press procedure had a mixture gas ratio between argon and hydrogen of 95:5 (common grade) at 1030 oC and a soaking time of one hour. The results were examined by comparing the electric resistivity property, apparent density, bulk density as well as the porosity percentage inside the work piece material. The results revealed that the optimum combination of percentage Cu-C-Ni element was Cu92-C3-Ni5 (%wt), leading to the satisfactory Copper distribution in most of the structure. The size of sub sieve powder after grinding was found to be 22-31 micron with an electric resistivity of 1.45829E-05 k-ohm*cm. The minimum porosity percentage was found to be 2.19 %. Therefore, the element properties were found to be suitable for using as an electrode in EDM work when compared to that of the electrode prototype (EDM C3).

The objective of this research is to study and compare quality milling surfaces, and the effects of plastic mould steels AISI-1050 and AISI-P20, in a milling process with various parameters based on experimental conditions, such as: 1) feed rates at 45, 50 and 55 mm/min, 2) spindle speeds of 510, 572 and 637 rpm, and 3) milling levels at 3, 5, and 10 mm, respectively, using a 10 mm twin flute ended type mill. The experimental results found that plastic mould steels which had the best quality milling surface were AISI-P20 and AISI-1050, with roughnesses of 2.627 μm and 2.120 μm, respectively. Quality milling surfaces were milled by using the most suitable parameter feed rate of 45 mm/min, a spindle speed of 637 rpm and a cut depth level of 3 mm, for both tested grades. However, characteristics of milling surfaces and wear of the mill end were directly influenced by changes of parameters for all test conditions. As a result, the quality of milling surfaces also changed.

The objective of this research is to study comparisons of Cu and CuZn electrodes, during Electrical Discharge Machining (EDM) of martensitic stainless AISI 410. The workpiece material was a rectangular plate, measuring 30x50x5 mm. The conditions of the EDM process were 3.0mm depth and 2.0 mm diameter, with variables of parameter being: currents, on/off-times and open circuit voltages of spark. Evaluation of the electrical discharge was conducted using Material Removal Rate (MRR), Electrode Wear Ratios (EWR) and Arithmetical Mean Roughness (Ra), respectively. The results found that CuZn electrode materials provide higher MRR and EWR than electrode materials of Cu. Also, when considering the melting of white layer, initial melts found that the white layer surface material is also good for the integrity of the state park, and it was additionally also found that when the current level increases, then that will rise accordingly.