Surface Integrity, Tool Wear, and Chip Morphology Studies in Spot Cooled Vibration Assisted Turning of Ti6Al4V Alloy

Surface integrity in the machining of Titanium alloys is of prime importance as they directly influence the service life of the machined component. It is usually affected by the process variables and type of process itself. In addition, tool wear also plays a crucial role in the determination of lubrication and cooling efficiency of the machining process adopted. This work deals with surface integrity, tool wear and chip morphological studies in machining Ti6Al4V alloy with an integrated in-house developed machining technique titled Spot Cooled Vibration Assisted Turning (SCVAT). The experiments were carried out at constant machining conditions to evaluate tool wear, residual stress and chip morphology whereas one factor was varied at a time for surface finish. Surface finish is measured by varying cutting speed, feed, amplitude and coolant pressure. The surface finish is improved by 35.71% with increase in amplitude and 43.75% with increase in coolant pressure. The residual stress is measured on the surface and depth wise up to a depth of 120 mu m and identified the compressive residual stress with proposed technique. Tool wear is reduced by 43.50% percent in SCVAT compared to conventional dry turning (CT). In addition, the study revealed that abrasion is the dominant mechanism causing tool wear in SCVAT. Chip morphology studies are also carried out and observed that the proposed technique is able to produce thin chips compared to CT.