Investigation of the Fluctuation Size in Thrust Force and Chip Morphology in Drilling

Abstract

Drilling is a widely used production method, having a broad range of applications taking part in machiningoperations. The length of the cutting edge of the drill causes variations in cutting speed, resulting in undesiredoutputs. In order to decrease this adverse impact in drilling, selecting higher point angles is an obligation,associated with three different kinds of feed rates and spindle speeds. The aim of this study is to investigatethe effect of feed rate, spindle speed, and point angle on the fluctuation size in thrust force besides the effectof the fluctuation size in thrust force on the surface roughness, tool wear and chip morphology. In conclusion,while higher point angles provided optimum outputs such as lower fluctuation size in thrust force, less toolwear, better surface quality and continuous chip form, the effect of feed rate and spindle speed on theseoutputs varied depending on each other. With the stability in fluctuation size in thrust force, less tool weartook place, and better surface quality and continuous chip form were achieved. However, due to the effect ofvibrations, higher fluctuation size in thrust force caused undesired outputs, such as poor surface quality, moretool wear, removal chip in short and brittle form during the drilling operations.