A Study on CVD Diamond Coated Cutting Tools Wear Performance using Vibration and Acoustic Emission Signals

Maximizing the use of cutting tool inserts and effectively utilizing them in the automated manufacturing process is critical to reducing machine down time and improving part quality. Early removal of tooling inserts can lead to less productivity and increased costs. Utilization of tooling inserts beyond its stipulated life time can cause dimensional inaccuracies and undesirable surface deterioration. Optimizing the cutting tool insert life will require an appropriate method for finding out remaining useful life of tooling inserts based on respective machining conditions. In this present work, acoustic signals and vibration signals were acquired during machining to monitor the tool failure. The change in signal variations in acoustic emission and vibration signals were correlated to the corresponding tool wear during machining. In this regard, machining experiments were performed on AA2124/25%/SiCp material using four different CVD Diamond coated tungsten carbide cutting tools (MCD-Microcrystalline diamond coating, NCD-Nano-crystalline diamond coating, BDD-Boron doped diamond coating, BMTN-Boron doped graded layer diamond coating) at an suitable cutting conditions. The results indicated that burst type AE signals observed in MCD and NCD coated tools correlated to chip entanglement, edge chipping, and the corresponding vibration analysis shows a similar increase in amplitude in the final cutting pass. However, there was no abnormality seen in BDD and BMTN coated tools signal variation which indicates least tool wear.