Experimental Determination of Optimal Speeds for Alloy Steels in Plane Turning

In machining, speeds play vital role. The operator should know exactly the speed at which machining should be performed to get the required surface finish. In this paper, an attempt is made to determine the optimal cutting speed for machining of alloy steels. Three work piece materials having different hardness are taken and machined using a round nose tool with a coated tip. The tool dynamometer is attached to the tool post for force measurement. Turning operation on the work piece is performed on lathe at four different speeds, keeping the feed and depth of cut constant. Cutting forces acting on the tool, temperature at the tool and material interface are recorded. Power consumed being determined by a wattmeter and surface roughness values are measured. The same procedure is repeated for the other two work-pieces materials and optimal speeds for machining are determined for the three specimens. The results obtained are compared with the theoretical values and found to be very close.