Experimental investigation of surface integrity after wire electro-discharge machining of Ti–6Al–4V

Abstract

This article presents the relationship of machining parameters containing pulse-on time (T on), pulseoff time (T off), peak current (IP) and servo voltage (SV) on surface integrity characteristics, including white layer thickness (WLT), heat-affected zone (HAZ) and surface crack density (SCD) and also on material removal rate (MRR), after wire electric discharge machining of Ti-6Al-4V. Taguchi's method was utilized to design the experiments, and response surface methodology (RSM) was employed for developing the empirical models. Results indicated that T on and IP played a significant role on surface integrity characteristics. In addition, the microstructure of selected machined samples was analysed using a field emission scanning electron microscope (FESEM) and energy-dispersive X-ray (EDX) analysis. Accuracy of models was examined using residual analysis and confirmation runs. Finally, multi-response optimization of process parameters was obtained using desirability approach. Results can be used to improve the quality of the machined workpiece significantly to fulfil the requirements of the various industries. The novelty of this research is mainly investigation and multi-response optimization of all the surface integrity characteristics at the same time.

Evaluation of the Surface Integrity and Recast Layer in Electrical Discharge Turning of WC-Co Composites

“…It is noteworthy that there is a slight increase in the copper content in the layer compared to the base material. In electrical discharge machining, the surface topography is characterized by sh craters, spherical particles, melted drops, globules of debris, voids, and cracks, whi created due to the high-heat energy released during the process, followed by rapid c [20]. Aiming to evaluate the effect of different rotational speeds on various machin gimes, the surfaces machined using EDT were studied.…”

“…In fact, the white layer is defined as the material that is melted by the electrical discharge and then re-solidifies on the workpiece surface. The peak current and the pulse-on time are known as the most significant parameters affecting the white layer’s thickness [ 20 ]. Increasing the discharge energy leads to an increase in the recast layer thickness [ 21 , 22 , 23 , 24 , 25 , 26 ].…”