Analyzing the effect of tool thickness on surface roughness and straightness in CNC parting operation of AA6063

Abstract

Surface roughness and straightness of AA6063 Aluminium alloy while performing experimental studies during the parting operation is discussed in this paper. The material and its standard dimensions were selected based on easy availability in the market and its application in ship and airplane industries. The selected material has diameter of 25 mm. Parting tool holder and inserts were selected with regards to their compatibility with the CNC machine. High-Speed Steel (HSS) square parting tool holder mounted by uncoated cemented carbide inserts of two different thicknesses, 3 mm and 4 mm were used. Parting operations were carried out on Gedee Weiler Eco Turn ET25 CNC machine using HSS square tool.Process parameters such as Tool thickness (A) (3, 4 mm), Speed (B) (1250, 1500, 1750 rpm), Feed rate (C) (3, 4, 5 mm/min) were varied to determine the results of the experimental study. It was concluded that better surface finish and degree of straightness were obtained at tool thickness of 3 mm, cutting speed of 1750 rpm and feed rate of 4 mm/min. Surface roughness testing was conducted using a Mitutoyo-SJ 210 Stylus-R5 profilometer. Surface straightness testing was conducted on Daisy 564 Cimtrix CMM.The findings indicated that the feed rate, followed by tool thickness and cutting speed, has the greatest influence on the surface roughness (Ra) characteristics of AA6063 material. While comparing the speed and feed in both tool thicknesses, it is observed that as we increase the tool thickness, there is an increase in both surface roughness and in the degree of straightness. The most favorable outcome obtained from the experiment shows that tool thickness 3 mm can be used for better surface finish and flatness.