Assessment of scatter on material properties and its influence on formability in hole expansion

The plastic deformation included in the technological processes of sheet metal forming allows the production of different components with different geometries. Therefore, the formability of metallic materials is an essential feature in stamping processes. One of the inevitable scattering sources when considering these processes is the variability of material properties, which can change from coil to coil, from batch to batch and from supplier to supplier. This constitutes a significant obstacle in improving the quality of any manufacturing process. The current study investigates the formability and the mechanical characterization of a defined advanced high strength steel grade, considering different suppliers, coils, and batches in order to evaluate its influence on the results of the sheet metal forming process. A microstructure analysis is also considered to understand the impact of micro-scale variables (e.g. grain size) in macro-scale behavior. Additionally, numerical simulations were taken into consideration to evaluate the influence of mechanical characterization in the results.