Abstract
The current study focuses on investigating the effect of milling parameters on the
microhardness during dry and flood milling of Ti-6Al-4V. Dry and flood milling were performed
while varying spindle speed (120, 150, and 180 rev/min), depth of cut (1, 1.5 and 2 mm), as the
feed rate (4.6 mm/min) was kept constant. Subsequent to milling, milled surfaces microhardness
were measured and microstructure evolution was analysed using an optical microscope. It was
established that the deformation of beta phase increased with increase of spindle speed during
dry milling while during flood milling there was no microstructural change associated to the
increase of the spindle speed. On the other hand, the hardness increased as result of increase of
spindle speed during both dry and flood milling. Flood milling generated a maximum hardness
of 338.44 HV at 180 rev/min which is superior to maximum hardness of 336.36 HV produced
during dry milling. Dry milling at 1.5 mm depth of cut generated maximum deformation of beta
phase while during flood milling maximum deformation was recorded at 2 mm depth of cut. The
hardness increased with increment of depth of cut during flood milling while it decreased with
increase of depth of cut during dry milling.