To study the influence of die clearance on the quality of non-oriented electrical steel parts, a high precision floating blanking die was designed for non-oriented electrical steel 50WW470 and 50WW800, which were commonly used in motor cores. The influences of die clearance on burr depth, springback and ovality were analyzed by systematic blanking experiments. The results show that the burr depth increases with the increase of die clearance, while in certain scope the springback decreases. Furthermore, the material mechanical properties and uneven distribution of residual stress result in ovality, the mechanical properties of material in perpendicular to the rolling direction are better than that in parallel to the rolling direction, and the residual compressive stress in parallel to the rolling direction is bigger than that in perpendicular to the rolling direction. Therefore, the springback of part parallelling to the rolling direction is greater, so the size of part becomes bigger. After annealing, the residual compressive stress decreases, and anisotropy of electrical steel reduces, so the ovality decreases by 10%-60%.
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