Determination of cutting condition for optimal tool-workpiece interface temperature in dry-turning AISI 1029 steel with carbide-insert tool by Taguchi’s method

Abstract

The AISI 1029 steel type is often used in the turning process to manufacture fasteners, studs, and other engineering components under the costly effects of high temperatures. The paper exemplifies the basic use of Taguchi's optimization method in selecting cutting conditions and determining at which condition the optimal tool-workpiece interface temperature occurs in dry-turning the steel type on the lathe with a carbide-insert tool. Turning experiments were performed on an XL 400 lathe with the steel type in accordance with the L-9 Latin squares arrays designed with 0.5, 1, and 1.5 mm-depths of cut; 0.1, 0.2, and 0.3 mm/rev-feed rates; and 125, 250, and 500 m/min-cutting speeds as selected inputs, and measured tool-workpiece interface temperatures as the outputs. The inputs and outputs were analyzed using the Minitab-17 software-generated signal-to-noise ratios, main effect plots, contour and surface plots, and variance analysis by imbibing Taguchi's philosophy of the smaller-the-better. The result showed that the optimal interface temperature within the turning conditions was 29.5oC at 125 m/min cutting speed, 0.1 mm/rev feed rate, and 1.5 mm depth of cut. The variance analysis at a 95% confidence level showed that the cutting speed contributed most to the temperature with an 88.15% value, followed by depth of cut with 5.33%, and feed rate with 33.33%. A validation test at the optimal cutting condition indicated 30.31oC as the optimal interface temperature with an error of only 2.7% relative to the 29.5oC-value obtained with the software's predictive regression equation.