Studying Performance of Wire Electrical Discharge Machining for Multi-pass Cutting Strategy on the Tool Steel SKD 61 Using Recommended Parameters of Machine

This research aims to study the machining efficiency of wire electrical discharge machining for multi-pass cutting. The recommended parameters of the machine are employed for cutting test tool steel grade SKD 61 with the thickness of 40 mm. The brass wire electrode with the diameter of 0.25 mm was used in the cutting test. The recommended parameters for multi-pass tool path cutting consisted of 4 operations. The 1st cut was defined as a full cut that required the removal of a large amount of workpiece material, with the cutting speed set at 2.60 mm/min. The 2nd, 3rd, and 4th cuts involve cutting on the edge of the workpiece to remove only a small amount of work material, with the cutting speed set at 3.20, 3.60, and 6.80 mm/min, respectively. The experimental test showed that the machining performance of the cutting speed for the 1st cut was lower than the expected value by approximately 18.01 percent. The 2nd, 3rd, and 4th cuts found that the cutting speed higher than expected value by approximately 104.34, 128.89 and 4.12 percentage for each cutting pass, respectively. In addition, the surface roughness and dimensional error of the machined part decrease as the number of cutting passes increases. The difference between the expected values and the experimental results is very useful in planning decisions and quality control for cutting workpieces by the process of wire electrical discharge machining.