New Method for Categorizing Low Carbon Automotive Sheet Steel

More stringent mechanical property requirements in automotive sheet steels, coupled with improvements in steel processing techniques, have made traditional methods for categorizing sheet steel obsolete. In particular, classification of steel quality by terms such as CQ, DQ and DQSK is no longer appropriate. SAE's Division 32 has addressed this issue and written a recommended practice for classifying sheet steel. The new method is based on nominal yield strength coupled with yield strength uniformity. Also included are provisions for differences in surface quality. The methodology has applicability to hot rolled, cold rolled, and coated sheets in the low to medium strength range.