This thesis presents the development of a test rig for determining the shear mechanical properties of thin sheet metals in the direction perpendicular to the sheet plane. Knowledge of this material response is important for sheet metal cutting, blanking, punching, fine blanking and mechanical joining processes, while it cannot be determined directly using conventional tensile and shear tests. Based on a review of existing testing methods, the requirements for a test rig were defined to enable stable and repeatable shear loading of thin sheet metals while reducing the influence of undesired bending and tensile loads. Two tool designs were developed, with the final design adapted for manufacturing by wire electrical discharge machining. The manufactured tool enables precise clamping and simultaneous symmetric shearing of two sheet metal specimens with a thickness of 0.3 mm. The tests were performed on a laboratory testing machine with simultaneous measurement of the punch force and displacement. The measured force–displacement curves exhibit the characteristic response of the shearing process, including the initial deformation of the material, attainment of the maximum force and its subsequent decrease until final separation of the specimen. The results confirm the suitability of the developed test rig for repeatable characterization of the shear response of thin sheet metals and provide a basis for further comparison of different materials and sheet cutting directions.
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