MACHINABILITY STUDIES OF WROUGHT TITANIUM ALLOY Ti-6Al-4V BASED ON ORTHOGONAL ARRAY DESIGN

Abstract

This research focuses on wrought Ti-6Al-4V machining using coated carbide inserts under flood cooling to study the machinability characteristics. Machining parameters are optimized, and mathematical models are developed for correlations. Surface roughness lies between 0.215[Formula: see text][Formula: see text]m and 0.830[Formula: see text][Formula: see text]m and even below 1[Formula: see text][Formula: see text]m during machining. Flank wear lies within 0.033–0.16[Formula: see text]mm which is below the 0.2[Formula: see text]mm criteria of wear. Cutting temperature lies between 31∘C and 158∘C. The reduction of cutting temperature and chip serration under flood cooling and the subsequent transfer of heat from the shear zones help to generate good surface finish and may be due to the evolution of a lower wear rate. Abrasion, chipping, adhesion and built-up-edge are seen as major mechanisms of wear. The optimal conditions are found to be a depth of cut of 0.1[Formula: see text]mm, 0.1[Formula: see text]mm/rev feed rate and 70[Formula: see text]m/min cutting speed. There is an improvement in results at optimal conditions of 38.42% for Ra, 60.86% for VBc and 27% for [Formula: see text], respectively, than initial parametric conditions. Further, grey relational grade has been improved by 0.263. Machinability models developed through quadratic regression are observed to be significant.