Investigation of The Effects of Processing Parameters on Measuring Accuracy in Electro Erosion Machining of Ti-6Al-4V Alloy

Abstract

Titanium alloys are one of the materials that are difficult to process due to their high strength, high hardness and low thermal conductivity, wherefore low tool life and surface quality and high energy consumption are involved in shaping them with traditional manufacturing methods. In particular, special tool geometries are required for the machining of complex geometry parts including helical groove, keyseat, micro-holes, etc. with traditional manufacturing methods, which leads to increases in machining costs. In such cases, non-traditional alternative processing methods are preferred. In this study, keyseat shaping procedures were performed according to DIN 6885 standard in the electro (die-sinking) erosion machine for Ti-4Al-6V alloy. As a result of experiments conducted in copper electrode and Belone EDM F dielectric fluid environment, the effects of different processing parameters (discharge current, pulse on time and pulse off time) on measuring accuracy were investigated. In addition, the effects of 3D surface and SEM images and processing parameters on the accuracy of the coordinate measurement were evaluated. With the low discharge current, less thermal energy is transferred to the workpiece and smaller particles are removed from the workpiece, obtained in closer results to the targeted values. The biggest difference between the targeted keyseat depth, width and length and the measured value was 18.13%, 4.24% and 0.625%, respectively. The results closest to the specified standard keyseat dimensions were obtained in Ip=9A, Ton=150μs, Toff=120μs processing parameters.

Keywords

• Electro erosion machining
• Ti-6Al-4V alloy
• keyseat
• measurement accuracy

Kaynakça

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