Optimization of Process Parameters of End Milling Process Using Factorial Design of Experiments

Manufacturing managers, schedulers, and engineers constantly try to overcome with the effects of cutting tool selection. Inaccuracy of cutting tool will contribute to poor surface finish, tool damage, chatter, dimensional accuracy and many other problems that contribute to low productivity and much time will be wasted.Some of the important process variables (cutting parameters) that effect the cutting force and surface roughness process are cutting speed, feed depth of cut and nose radius (cutting tool diameter). In order to optimize the output parameters i.e., cutting force, power consumption and surface roughness, the process variables are varied. The design of experiment is the procedure of selecting the number of trails and conditions for running them, essential and sufficient for solving the problem that has been set with the required precision. In the present work two factorial design of experiments (DOE) technique is used in order to find the effect of input parameters on cutting force and surface roughness. In the present work milling process is carried out for the work material EN8 and cutting forces are measured using dynamometers at DMRL. In design of experiments, number of trails to be conducted is determined by factorial method and design matrix is constructed. After getting the design matrix, regression coefficients are calculated. Adequacy of model is tested by fisher test at 5% significance level. Student's t-test is carried out to check the significance of each regression coefficient. Contribution of each factor on output is determined by Analysis of Variance (ANOVA) and using MAT LAB software the optimum values of cutting force and surface roughness corresponding to their process parameters are obtained.