Abstract
Ultrasonically Assisted Turning (UAT) is a progressive machining method in which vibration is applied to the cutting insert in the direction of the cutting tool velocity to reduce the cutting forces significantly and increase the surface finish noticeably. However, the key question about the tool damage caused by the vibration and its effect on the cutting forces, surface roughness, and process zone temperature is still unknown in UAT. This paper conducts an experimental analysis of the effect of a worn tool in UAT and Conventional-Turning (CT) of beta-Ti-15V-3Al-3Cr-3Sn (Ti-15333) alloy on the surface quality of a machined surface, temperature of the process zone, and cutting forces using KC5510 (PVD TiAIN) and CP500 (PVD (Ti,Al)N-TiN) cutting inserts. In UAT, the tool edge damages in CP500 inserts increased with tested machining time, which resulted in the growth of 8 N and 10 N in tangential force component in CT and UAT, respectively. Similarly, with the progression of tool edge damage, growth rates of 1.7% and 9.3% in the process zone temperature were observed in CT and UAT, respectively. The surface roughness results revealed a gradual degradation with machining time; however, the results of UAT with a worn tool were significantly better than those of CT with a virgin tool. (C) 2019 Sharif University of Technology. All rights reserved.