The device for preparing sheet specimens comprises a base (1) for placing on it a sheet specimen (2) and a cutting punch (3) for cutting sheared cracks or sharp notches in said sheet specimen (2). Preferably, said cutting punch (3) comprises a beveled lower end (31) and/or a central vertical groove (32). Permits the cracks to be formed cutting directly the sheet, and not by cyclic loading, so that the preparation of the sheet specimen takes a reduced time in comparison with the conventional devices.

The present disclosure relates to a method for predicting the occurrence of electrode crack and delamination, and the objective of the present disclosure is to provide a method for predicting the occurrence of electrode crack and delamination, the method comprising: measuring crack force for a dried electrode; and predicting the occurrence of crack and delamination of the electrode on the basis of the measured crack force.

To further enhance the evaluation accuracy of a delayed fracture. Focusing on the fact that a calculated stress value serving as the reference for the occurrence of the delayed fracture changes depending on analysis conditions of a forming analysis, a value obtained by changing a stress value serving as the reference for the occurrence of the delayed fracture according to the analysis conditions for analyzing an intended formed article (article for practical use) is used as the reference for evaluating the delayed fracture. For example, analysis conditions of a forming analysis in an evaluation test of the delayed fracture are matched with analysis conditions of a forming analysis of an article for practical use represented by an actual automobile component.