On the Volumetric Assessment of Tool Wear in Machining Inserts With Complex Geometries—Part II: Experimental Investigation and Validation on Ti-6Al-4V

In part 1, traditional methods of tool wear characterization were qualitatively assessed, and consequently a volumetric approach of wear quantification was developed, standardized, and evaluated using a gauge R&R study. The objective of this paper is to experimentally investigate and validate this assessment methodology using the wear results from a series of controlled machining experiments on grade-5 titanium alloy. The traditionally difficult-to-machine alloy, Ti-6Al-4V, was specifically chosen as the work material in order to highlight how the use of this assessment methodology is necessitated especially because of (i) the pronounced complexities in the geometric profiles of typical cutting tools employed for machining Ti-6Al-4V and (ii) its nonconformity in behavior with standard tool wear models, such as the Taylor’s tool life model and its extensions. This assessment methodology is then validated through the simultaneous analysis and comparison of traditional flank wear and associated photomicrographs with volumetric wear and its evolution. Furthermore, the concept of the M-ratio and its derivatives are developed to quantify the efficiency of the cutting tool during each pass at a constant material removal rate (MRR).