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This paper aims to focus on analysing the wear characteristics of tungsten carbide tools on which various micro patterns are fabricated to study its effect on the machinability of Ti-6Al-4V at dry turning conditions.

Micro-patterns such as dimples, linear grooves and a novel combination of dimples and linear grooves were fabricated on rake faces of uncoated tools by micro-EDM process. Impact of these patterns on tool wear and chip morphology characteristics under dry machining conditions were analysed, and their performances were compared with the non-textured tool (NTT).

Encouraging results in terms of minimal tool wear and favourable chip morphology characteristics were observed in case of all the textured tools, which demonstrated better tribological characteristics in contrast to NTT. The average flank wear was reduced by 43.5, 32 and 24.7% in dimple textured tool (DTT), linear textured tool (LTT) and hybrid textured tool (HTT), respectively, as compared to NTT. The average chip curl diameters measured for NTT, DTT, LTT, and HTT were observed to be 6.60, 3.51, 4.0 and 4.31 mm, respectively.

The contribution of this work lies in fabricating innovative patterns using cost-effective micro-EDM process and analysing how the patterns, depending upon their dimensional area and wear debris accumulation characteristics, influence the machinability of Ti-6Al-4V in the absence of any lubrication mediums.

Electrical discharge machining (EDM) is well-known for its credibility in the processing of advanced materials, which are electrically conductive. The strenuous effort associated with machining of Ti6Al4V (Ti64) using conventional methods, and its low tribological behavior, present an immediate need to develop solutions to monitor and improve the compatible techniques such as EDM.

The present work includes following: monitoring the ED process parameters, namely, current (I) and pulse on time (T_on), in controlling the material removal rate and surface roughness (R_a and S_a) for development of tribo-adaptive surfaces; and investigation on the role of oxides pertinent to the tribo-behavior of Ti64 (bare and EDMed) surfaces.

The tribological behavior of Ti6Al4V surfaces got remarkably improved through ED machining, which points to the credibility of the process to establish itself as a surface alloying technique. The recast layer (RL, alloyed matrix) acted as a protective coating; stable enough to assist the developed tribo-oxides such as TiO and Ti₈O₁₅ in rendering improved sliding performance at load = 50 N and speed = 0.838 ms⁻¹.

The surface modification through ED machining was experimentally proven to improve the wear behavior of Ti6Al4V surfaces.