Rotationsbiegeversuche

Rotationsbiegeversuche, also known as rotary bending fatigue tests, are a method used in materials science and engineering to determine the fatigue strength of a material. This type of test subjects a specimen to a rotating bending load, which results in a cyclical stress pattern across the material. The specimen is typically a cylindrical rod, fixed at one end and subjected to a bending moment at the other, which rotates at a constant speed. This rotation causes the top surface of the specimen to experience tensile stress while the bottom surface experiences compressive stress, and vice-versa as it rotates.

The primary objective of a rotationsbiegeversuch is to find the fatigue limit or fatigue strength of the material. The fatigue limit is the stress level below which a material can theoretically withstand an infinite number of load cycles without failing. Fatigue strength, on the other hand, is the stress a material can withstand for a specific, finite number of cycles. During the test, the specimen is subjected to a known stress amplitude, and the number of rotations until failure is recorded. By conducting tests at various stress levels, a stress-life (S-N) curve can be generated, which plots stress amplitude against the number of cycles to failure. This curve is crucial for understanding a material's behavior under cyclic loading and for designing components that will not fail prematurely due to fatigue. Rotationsbiegeversuche are widely employed in the automotive, aerospace, and mechanical engineering industries for material characterization and quality control.