PULSED LASER SURFACE MODIFICATION OF CUTTING INSERTS FOR ENHANCED MACHINING CAPABILITIES

Abstract

In this investigation, the KrF pulsed excimer laser (pulse energy: 350 mJ/pulse, wavelength: 248 nm, pulse duration: 30 ns, repetition rate: 5 pulse/sec and number of shots: 1400) was used for the pretreatment on the rack face of TiN and TiAlN coated tungsten carbide inserts. The evolution of surface morphology of pretreated cutting inserts with different number of shots for specific pulse energy was measured by scanning electron microscope (SEM). Then dry cutting test carried out by these laser pretreated TiN and TiAlN coated cutting inserts and the conventional inserts (without laser pretreated) on mild steel. After performing cutting test, both laser irradiated and conventional tools show same wear pattern but wear of conventional tool is more as compare to that of laser irradiated tool. Results show that cutting forces found to be low in case of cutting performed by laser pretreated inserts and surface roughness of the workpiece improved which was machined by laser irradiated tool.