Surface and Subsurface Quality of Titanium Grade 23 Machined by Electro Discharge Machining

Abstract

Electrical Discharge Machining (EDM) is a non-traditional cutting technology that is extensively utilized in contemporary industry, particularly for machining difficult-to-cut materials. EDM may be used to create complicated forms and geometries with great dimensional precision. Titanium alloys are widely used in high-end applications owing to their unique intrinsic characteristics. Nonetheless, they have low machinability. The current paper includes an experimental examination of EDM’s Ti-6Al-4V ELI (Extra Low Interstitials through controlled interstitial element levels) process utilizing a graphite electrode. The pulse-on current (IP) and pulse-on time (Ton) were used as control parameters, and machining performance was measured in terms of Material Removal Rate (MRR), Tool Material Removal Rate (TMRR), and Tool Wear Ratio (TWR). The Surface Roughness (SR) was estimated based on the mean roughness (SRa) and maximum peak to valley height (SRz), while, the EDMed surfaces were also examined using optical and SEM microscopy and cross-sections to determine the Average White Layer Thickness (AWLT). Finally, for the indices above, Analysis of Variance (ANOVA) was conducted, whilst semi-empirical correlations for the MRR and TMRR were given using the Response Surface Method (RSM). The results show that the pulse-on time is the most significant parameter of the machining process that may increase the MRR up to 354%. Pulse-on current and pulse-on time are shown to have an impact on the surface integrity of the finished product. Furthermore, statistics, SEM, and EDX images on material removal efficiency and tool wear rate are offered to support the core causes of surface and sub-surface damage. The average microhardness of the White Layer (WL) is 1786 HV.

An Optimalization Study on the Surface Texture and Machining Parameters of 60CrMoV18-5 Steel by EDM

“…Nevertheless, the intuitive hypothesis that higher machining power and/or per-pulse energy will automatically lead to a higher MRR is incorrect, mainly because of three underlying mechanisms: the plasma channel growth, the debris concentration in-between the electrode and the workpiece, and the carbon decomposition. More specifically, as the plasma channel expands (e.g., for higher pulse-on times) it consumes a significant amount of energy, while at the same time, the energy density is decreased [ 1 , 3 , 26 ]. Moreover, the increase of the MRR results in a higher debris concentration in-between the electrode and the workpiece, a concentration that impacts the flushing efficiency.…”

“…The total material removal accumulates thousands or even millions of successive sparks [ 2 ]. The inherent advantages of EDM render it a feasible process, widely utilized in a modern industrial environment, namely, in automotive and aerospace industry, for tool and molds manufacturing, as well in the medical field, where surgical components and implants are produced with EDM [ 3 ].…”

Overview of Surface Modification Techniques for Titanium Alloys in Modern Material Science: A Comprehensive Analysis

“…This method achieves material removal by applying a regulated electrical pulse between the tool electrode and the workpiece specimen [72]. The EDM setup is shown in Figure 14 [73].…”

“…This method achieves material removal by applying a regulated electrical pulse between the tool electrode and the workpiece specimen [72]. The EDM setup is shown in Figure 14 [73]. The surface quality and machining efficiency of EDM are mainly affected by the electrode material and pulse on conductive current.…”

“…EDM can be used to fabricate complex shapes and geometries with high dimensional The surface quality and machining efficiency of EDM are mainly affected by the electrode material and pulse on conductive current. Panagiotis et al [73] found that the effect of pulse on conductive current (IP) and pulse on time (Ton) on the material removal rate is significant by comparing the effect of pulse on conductive current (IP) and pulse on time (Ton) on the material removal rate. Ahmed et al [74] found the effect of pulse on conductive current (IP) and pulse on time (Ton) on the material removal rate of α-β titanium alloys by exploring the effect of tool electrode on the machinability of EDM.…”