Experimental/analytical comparison of three-dimensional deformations at the tip of a crack in a plastically deforming plate II: material characterization and finite element analysis

This paper is the second of three devoted to a detailed study of the three-dimensional deformation at the tip of a notch in a ductile steel plate loaded in three-point bending. A finite element model has been constructed preparatory for a comparison with the experimental data in the subsequent paper; the geometry and material properties have been carefully matched to the experiment described in a preceding paper. The experiments to provide the complete description of the relevant material behavior are presented, followed by the details of the numerical model and some sample results. Young's modulus and the yield behavior are evaluated. Because any error in Poisson's ratio induces an error of the same order of magnitude in the three-dimensional elastic displacement field, this quantity is also measured with moire interferometry to within ±1 percent. Also, besides matching the material properties and geometry of the numerical model to the three-point-bend experiment, the development of (tunneling) fracture within the interior of the specimen is determined; these measurements are incorporated into the numerical model by releasing appropriate nodes.