Abstract
In the present work, coated and uncoated carbide tools were used for milling Ti-6Al-4V ASTM B348 under wet cutting condition. The cutting speeds selected for the experiment were 80, 120, and 160 m/min with the feed are at 0.1 mm/tooth. The depths of cut applied were 1.0 and 2.0 mm. From chip cross section and microstructure investigation using optical microscope and scanning electron microscopy (SEM), at the highest cutting speed and lowest depth of cut, the smallest value of chip fluctuation factor can be attained. At this condition the chips are stable with lower vibration. A transition from aperiodic to periodic saw-tooth chip formation occurring with increases in depth of cut and cutting speed. The chip micrograph shows the reduction in secondary deformation zone thickness induced by the coated insert cutting is evidence of reduced friction between the tool rake and the chip.The crack which determines the serrated chip during cutting operation, always occurs in the primary shear zone on the tool tip side.
