A novel approach to finding optimum operating conditions of design factors for the grinding experiment

The efficiency of grinding experiments is an important issue for many industries. In this paper, a central composite design-based methodology was proposed to investigate the four design factors that affect the particle sizes. The four design factors were specified as mill speed (% of Nc), ball filling ratio (fc), powder filling ratio (jb) and grinding time (min). Another important issue was how to obtain an optimum operating condition for four design factors. For this particular purpose, a novel dual response optimization model was proposed using the particle sizes (d 10, d 50, and d 90) and the span value concept. This proposed approach was compared to the desirability function-based optimization concept. The verification study of the experiment was also carried out. The results of the grinding experiment runs showed that the optimum operating conditions were mill speed 73.495% of Nc, ball filling ratio 0.354, powder filling ratio 0.157, and grinding time 70 min. In addition, d 10, d 50, and d 90 were found 3.31 µm, 12µm, and 45.6 µm, respectively. The span value was also found at 3.52.