Effect of cutting forces and vibrations on surface roughness on turning of AISI 1040 steel

In this study, It was tried to determine the optimum cutting parameters thanks to detailed research by examining the influences of cutting force and cutting tool vibrations on surface roughness during lathe dry turning process. Machining tests were performed using cementide carbide cutting tool which has from (CNMG 120404-NM KLP 115). The machining tests were carried out at three different cutting speeds (87 m/min, 143 m/min, 238 m/min), at three different feed rates (0.052 mm/rev, 0.104 mm/rev, 0.156 mm/rev) and at three different depth of cut (0.5 mm, 1 mm, 1.5 mm). Using 250 mm length and 50 diameter AISI 1040 steel as workpiece were carried out total of 27 machining tests. Cutting forces and vibrations were measured during the process. Surface roughness values of the machined surface were measured from five different point on the workpiece after mechanic tests. Then the average surface roughness values were measured. According to the measured values were evaluationed relation between vibration and surface roughness. Also, measured cutting force thanks to dynomometer on machining tests under different cutting conditions were analysied by Dynoware programme and measured vibration values thanks to acceleration were analysied by Labview programme. In addition, FFT chats (Fast Fourier Transform) were set up on Matlab to examine measured cutting tool vibrations at which frequency and at which amplitude. Surface roughness increased when vibration increased. This shows the effect of vibration is negative effect over the surface roughness.