Multi-response optimization in cutting mild steels

Abstract

Machine tools are very important metal cutting process that used widely in manufacture/construction and energy sector. Material removal rate in any metal cutting process is very important because it significantly affects the production rate, generated energy/forces, tool life. Improper choice of the machine tools, cutting tools or parameters will lead to be produced early wear, more energy and deterioration of surface qualities of machined mechanical components. The cutting process should be controlled during cutting or shaping process. In this study, therefore, multi-response optimization is carried out on AISI 1040 hardened mild steels when machined with ceramic cutting tools using response surface methodology under different cutting conditions. It can be noted that there are two responses. One is the surface roughness (SR) while the second is the material removal rate (MRR). The experimental results exhibits that all three factors reveal significant influence on generating metal cutting energy. Optimal levels are found out in A3, B3 and C3 level. Namely; cutting tests are carried out at 170 m/min cutting speed, 0.15 mm/rev. feed rate and 0.5 mm depth of cut conditions in terms of multi response performance index (MRPI). Analysis of variance and Pareto chart indicate that besides basic factors, A × C, A × B, B × C interactions have also an influence on MRPI (combination of MRR with SR). It is concluded that the correlation coefficient is found about 99.06%. Therefore, MRPI approach is capable of providing good modelling results for the combination of SR and MRR.