During heat treatment, the unalloyed C45E was austenitized at T = 850°C and then cooled to RT in a controlled manner, resulting in a predominantly ferritic-pearlitic microstructure with a Vickers hardness of HV10 = 216 [4,5]. In the tensile test, the material reached a maximum strength of Rm = 710 MPa and exhibited a yield strength of Rp0.2
A normalized unalloyed steel of grade C45E was used as the test material. The specimens were machined from round material with a length of 5,000 mm and a diameter of 20 mm and subsequently polished to a roughness value of Rz < 6 µm. The chemical composition according to the manufacturer's specifications corresponds to the specified limit value
Experimental setup and material
The stress-controlled single-stage tests were carried out on a Shimadzu type EHF-U servo-hydraulic test system with a maximum load of 50 kN, a frequency of f = 5 Hz, a sinusoidal load-time function, and a load ratio of R = -1 at room temperature with RT = 25°C.
The specimens were stressed to failure or to reach th
Introduction
Weight-optimized component design and the resulting estimation of the service life or service life of metallic materials require a comprehensive understanding of fatigue processes and the systematic investigation of fatigue behavior. For reasons of time and cost alone, many components can usually neither be built as prototypes nor tes
