Drilling process optimization by using fuzzy-based multi-response surface methodology

In this study, a fuzzy mathematical model is developed using a multi-response surface methodology with fuzzy logic to optimize all response variables simultaneously. The model has the flexibility to weight the response factors depending on the decision maker's choices. The model has been applied to the drilling process using a high speed steel drill bit on PVC samples in an upright drill. The aim of the study is to minimize surface roughness and cutting forces. The input variables and their experiment intervals are determined as cutting speed (360-1080 rev/min), feed rate (0.10-0.30 mm), and material thickness (15-45 mm). Surface roughness, radial force-X and radial force-Y are chosen as response variables. According to the experiments and statistical analysis, the optimum levels of cutting speed, feed rate, and material thickness were calculated as 1068 rev/min, 0.1195 mm, and 21.33 mm respectively.