Development of novel cutting tool with a micro-hole pattern on PCD insert in machining of titanium alloy

The development of a novel cutting tool that had a micro-hole pattern on their rake and flank face of cutting tool surface has found wider potential in the field of manufacturing. Micro-hole pattern features on a tool rake face help in controlling the tribological characteristics of the cutting tool. Micro-holes with the different number of holes orientation, diameter and depth were fabricated using the advanced application of the electrical discharge super drilling machine with the view to assist lubricant penetration and retention. A comparative study has been conducted between micro-hole patterned Polycrystalline Diamond (PCD) cutting insert and the commercially available PCD cutting insert. The effect of micro-hole pattern on the machining of Titanium alloy (Ti-6Al-4 V) is investigated with the application of the Minimum Quantity Lubrication (MQL) method in turning operation. Vibration signals were captured in feed force direction and measured using the tri-axial accelerometer. The cutting temperature, tool-wear, and chip-morphology were measured with an infrared thermometer and Scanning Electron Microscope (SEM). It was found that micro-hole textured inserts reduced the friction on the rake face resulting in the decrease of vibration up to 30-50%. The cutting temperature, tool wear and surface roughness were reduced to 30%, 50% and 40%, respectively. The conical and helical chips were produced in micro pool lubrication system. The friction coefficient can be minimized at the tool-chip interface by using liquid lubrication method. There is no unfavourable effect on the performance of cutting tools having holes on the cutting tool surface. All these parameters led to the improvement in the tool life.