Using surround DIC to extract true stress–strain curve from uniaxial tension experiments

The exact stress–strain curve can be directly identified from uniaxial tension experiments up to the point of onset diffuse necking. To gain insight into post-necking hardening response metals, other experimental methods such as bulge, compression or torsion are typically employed. Here, we introduce idea using surround DIC obtain accurate specimen shape measurements tensile specimens with rectangular gage section. Based on results a series detailed three-dimensional finite element simulations ASTM E8 type wide spectrum steel and aluminum behaviors, it is proposed combine history axial strain surface at center average stress extract for strains true 1. estimation uncertainty this procedure same order that associated uncertainties. This result validated through an additional computational study more than 100 distinct behaviors. Furthermore, system composed four stereo systems built used determine 1.5 mm thick DP780 steel. In addition, bulge performed material revealing good agreement behavior determined testing.