INVESTIGATION OF THE EFFECT OF CUTTING PARAMETERS ON SURFACE ROUGHNESS AND CHIP FORMATION IN DRILLING OF INCONEL 718 SUPER ALLOY

In this study, the effects of cutting parameters on surface roughness and chip formation obtained during the drilling of inconel 718 super alloy with coated and uncoated carbide drills were investigated. drilling tests were performed using tin and tialn coated carbide drills on a vertical cnc machining center with four different cutting speeds (10, 12,5, 15, 17,5 m/min ) and three different feed rates (0,05, 0,075, 0,1 mm/rev). blind holes with 8 mm depth were drilled with 5 mm diameter drills. surface roughnesses evaluation of holes based on the cutting tools was made with respect to the roughness measurements. according to this evaluation, the best results for surface roughness on the holes were obtained with the ones drilled by uncoated carbide tools. when the chip formations were examinated, for all tests the chip formations for the first drilled holes were a discontinuous chip form or tight helical chip form.