零件表面起皱,即坯料在变形时失稳,是常见的冲压缺陷。零件起皱影响产品外观,是不允许的。预防起皱是提高产品质量的重要因素。冲压件在凹模的压料表面上形成折皱1(图1)最为常见,有时这种折皱可延伸到冲件的底部与侧壁交接的圆角处。 冲压有倾斜侧壁的零件,其侧壁靠凸、 Parts of the surface wrinkling, that the instability of deformation in the blank, is a common stamping defects. Parts wrinkles affect the appearance of the product is not allowed. Prevention of wrinkling is an important factor in improving product quality. It is most common for the stamping to form a crease 1 (FIG. 1) on the die surface of the die and sometimes this crease can extend to the fillet where the bottom of the stamp engages the side wall. Stamping the parts with sloping sidewalls, the sidewalls by convex,