MODELING OF ROLLABILITY OF SURFACE DEFECTS DURING COLD ASYMMETRIC ROLLING

This paper presents the results of finite element modeling of the rollability of the most common surface defects (scratch, puncture, pressure) during cold rolling under symmetrical and asymmetric conditions with an asymmetry coefficient from 1 to 16. A steel strip with a thickness of 3 mm was used as an initial blank. The three surface defects were created on the surface, all defects had a depth of 0.5 mm. It was revealed that complete closure of all the defects studied during symmetrical rolling occurred only when initial blank was compressed by 80% higher (0.9 mm) than the initial defects depth. When using asymmetric rolling, an additional compression of 20% (0.6 mm) and an asymmetry level of 8 were required. Thus, asymmetric rolling can be considered an effective way to eliminate surface defects of a cold-rolled strip while providing a significantly lower compression level compared to symmetrical rolling.