As the science and our understanding of the physical properties of materials that we use for design progresses, as well as ecological and economic use of these materials, the demand for biaxial fatigue testing of mechanical components is increasing. Standardized uniaxial testing tends to produce inaccurate results, mostly because of anisotropic distribution of physical properties inside certain materials. In addition, biaxial testing is becoming predominant for analyzing components that are designed for multiaxial stress state. Such stress distribution causes material failure at lesser loads, as opposed to those, determined with uniaxial testing. For the aforementioned reasons, we designed a cost-effective and long-lasting biaxial test stand for determining low-cycle fatigue properties of test subjects. At the beginning of this master thesis, biaxial out-of-phase fatigue as a phenomenon and some existing solutions for such testing are introduced. Next, the process of developing and optimization a of new test stand according to DIN-VDI 2221 guidelines is presented in detail. For all components that are loaded the most within the technical system, both stress and deformation analyses have been conducted. The results of these analyses are presented in the conclusion, confirming the proper function of the newly designed test stand, in full accordance with the criteria of this assignment.
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