Optimization of pickling and annealing parameters in cold rolling using the Taguchi method

Abstract

AbstractIn this study, the optimum values of pickling and annealing parameters in cold rolling were obtained by using the Taguchi method. The materials taken from the hot rolling mill were subjected to pickling with different pickling times (3 min, 4 min, 5 min) parameters and then cold rolled. After this process, annealing was carried out with different annealing temperatures (700 °C, 750 °C, 800 °C), annealing times (5 min, 7.5 min, 10 min) in order to eliminate the cold working hardness. After these processes, sheet materials were subjected to skin‐pass rolling, which is the last step of the rolling process. Optimum conditions are minimum rolling force measured from the load cell positioned on the work rolls. In this direction, S/N ratios with objective function “smaller is better” and were calculated and the optimum levels of the parameters were determined as 3 min pickling time, 750 °C annealing temperature and 10 min annealing time. In line with the findings obtained from the analysis of variance, it was determined that the most important parameter was the annealing time with a rate of 48.99 %. Confirmation experiments were carried out and it was concluded that the optimization was valid.