Monitoring of EDM parameters to develop tribo-adaptive Ti6Al4V surfaces through accretion of alloyed matrix

Abstract

Purpose 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. Design/methodology/approach The present work includes following: monitoring the ED process parameters, namely, current (I) and pulse on time (Ton), in controlling the material removal rate and surface roughness (Ra and Sa) for development of tribo-adaptive surfaces; and investigation on the role of oxides pertinent to the tribo-behavior of Ti64 (bare and EDMed) surfaces. Findings 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. Originality/value The surface modification through ED machining was experimentally proven to improve the wear behavior of Ti6Al4V surfaces.

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