Optimization of the Car Body Elements’ Stamping Process Based on the Strain Analysis

The extent of deformation in the process of forming body elements affects the amount of thinning of the shaped material, and consequently the possibility of material cohesion loss. In the tests, the size of deformation of the car body elements in the stamping process was determined according to the measurement of the displacement of the measurement points. A measuring grid was applied to the surface of the mat by electrochemical etching. The form with the applied measuring grid was drawing on the production line. Reference point displacement measurements were made with the use of an optical measuring system. The forming limit curve was determined for the CR4 grade steel sheet with a thickness of g = 0.75 mm. The deformation measurement results were related to the forming limit curve to identify the actual deformation level. The results of the deformation measurement allowed to indicate the place and scope of the correction of the shaping tools geometry and process parameters.