Measuring applied force and energy consumption in deep drawing die Sets: An experimental and numerical analysis of CrN and CrTiN PVD coating effects

Excessive forming loads ultimately result in wear during the deep drawing process. This study uses an innovative test rig on a universal testing machine to monitor force-time variations during deep drawing. The rig captures force changes, workpiece/die friction, and energy consumption. The research explores how varying friction coefficients between the die and workpiece, lubrication conditions, and different PVD coatings on the die surfaces affect production performance in deep drawing. Various coatings were applied to 1.2379 cold work steel samples, and their friction behavior was examined. The performance of PVD-coated die sets was evaluated through experimental and numerical methods. The abrasive wear test revealed that the CrN coating had 46 % less wear volume than uncoated specimens. In contrast, the CrTiN coating showed 70 % more abrasion volume at 15 N load and 96.4 % less at 30 N load compared to CrN. Adhesive wear tests demonstrated that CrTiN had 9.09 % less wear at 6 N load and 27.66 % less at 10 N compared to CrN. Numerical simulations explored friction's impact on deep drawing; CrTiN die set used least energy, forming with lowest max force, while CrN set reduced max force by 0.56 %. CrTiN coating showcased better wear resistance, lower forming forces, and reduced energy consumption than CrN and uncoated dies under various friction conditions.