Analysis of a Plate of High Strength Steel: Simulation of Impact and Determination of Residual Stresses

Sammanfattning: In this study a finite element model has been created in ABAQUS/Standard in order to replicate impact tests performed by SSAB and to determine residual stresses in a plate. Uniaxial tensile tests have been done in order to determine the plastic behaviour of a high strength steel from the manufacturer SSAB and to determine whether the material can be assumed to be isotropic. Test specimens in the rolling and cross-rolling direction were cut out from an undeformed plate. The data was fit to a Voce hardening law which showed that the material is not isotropic due to different initial yield stresses. However, the hardening curve can be regarded as isotropic due to small differences between the rolling and cross-rolling direction. Vickers hardness tests have been done on three test specimens cut out from a deformed plate which has been used in the impact tests at SSAB. These Vickers hardness tests have been done in order to verify the finite element model. The Vickers hardness determined from experiments was compared to the calculated Vickers hardness from the finite element simulation. The comparison showed good agreement between experiments and simulations seeing that they follow the same trend. This indicate that the finite element model is a good numerical method to determine residual stresses in high strength steels subjected to significant plastic deformation.