Residual Stresses Determination with Incremental Hole-Drilling Method and FE Simulation in Sheet Metals Produced by ECAR

The incremental hole-drilling method is an effective technique for the measurement of the through- thickness residual stress distribution in the metal sheets processed by the equal channel angular rolling (ECAR). The ECAR is one of the SPD processes, which can develop a shear deformation into a sheet metal. In this process, internal stresses are created due to the different strain levels experienced in different locations at same time. In this study, the residual stresses as the macro stresses have been considered by the help of the incremental method and FEM for numerical calculation of the calibration coefficients. In addition, the FE simulation has been used to investigate the residual stresses distribution through the thickness. It was observed that the stress profile is not uniform through the material thickness and it variants from tensile to compressive. A comparison between the hole-drilling measurements and the FE simulation results showed good agreement.