Necking progression in tensile specimens monitored in real-time by using fringe projection

A specimen subjected to uniaxial tensile tests undergoes a thickness reduction that leads to out-of-plane displacements. These can be approximated by monitoring the progression of the changes in shape induced on the specimen. The combination of the fringe projection technique and the Fourier transform method (FTM) allowed us to monitor in real-time the out-of-plane displacement fields, induced on a brass sheet specimen in different regions of the tensile test. These maps enabled us to detect different trends in the deformation process and nonlinear effects linked to the progression of the thickness necking. Methodological details are provided below.