Investigation of monolayer alcrn coated and uncoated wc inserts on turning of ti 6al 4v alloy under wet and cryogenic coolant

Abstract

Difficult to machine material that are generally considered as tough for machining find varied use in the engineering fields. Industries aim to produce high productivity and good quality products at all cost. The major problems observed in machining parts are due to the temperature rise in the cutting zone. It leads to frequent failure of the cutting tool and dimensional inaccuracy of the components. The main reliability lies in the use of coolant in turning and various hard materials coating, on tool insert for the purpose of machining difficult-to-cut materials. An attempt in the turning has been made to reduce the cutting temperature in the cutting zone. This is done by developing new coating on carbide cutting insert and machining under various cooling environments. In this research work, a mono-layered AlCrN based coating on the tungsten carbide (WC) insert was developed using the physical vapour deposition technique. The coated cutting tool insert characteristics, such as Micro-hardness, coating thickness, surface morphology and elemental composition of the coating were studied and compared with uncoated cutting insert. newlineThe turning of Ti-6Al-4V alloy was carried out under conventional cooling (wet) and cryogenic cooling (cryo) environments using uncoated (CNMG 120408 THM), and AlCrN coated carbide inserts. The coolants were supplied directly at the cutting zone during turning operation. Turning of workpiece at three different cutting speed (90 m/min, 135 m/min and 215m/min), feed rate (0.102 mm/rev, 0.159 mm/rev and 0.205 mm/rev) and depth of cut (0.5 mm, 1 mm and 1.5 mm) were used newline