Inhaltszusammenfassung

The fatigue behavior of railway wheel steels has been investigated in the Very High Cycle Fatigue regime until 2•10E8 cycles under stress-controlled fully reversed axial loading at a frequency of 200 Hz at room temperature. Specimens machined from original wheels of SAE 1050 widely used in Germany for high-speed passenger traffic exhibit a distinct change in the slope of the S-N (Woehler) curve at about 2•10E6 cycles. Temperature and electrical resistance of the individual specimens are direc...The fatigue behavior of railway wheel steels has been investigated in the Very High Cycle Fatigue regime until 2•10E8 cycles under stress-controlled fully reversed axial loading at a frequency of 200 Hz at room temperature. Specimens machined from original wheels of SAE 1050 widely used in Germany for high-speed passenger traffic exhibit a distinct change in the slope of the S-N (Woehler) curve at about 2•10E6 cycles. Temperature and electrical resistance of the individual specimens are directly influenced by deformation-induced changes of the microstructure and are qualified to characterize the actual fatigue state in detail, even at very high test frequencies. On the basis of Morrow, Coffin-Manson and Basquin equations, a physically based lifetime calculation “PHYBAL” was developed. The S-N curve calculated on the basis of temperature and electrical resistance data measured after 10E4 cycles, corresponding to a test running time of only 50 seconds, matches well with the experimental S-N data. Crack initiation was observed at the specimen surface as well as in the bulk. » weiterlesen» einklappen

Autoren

Klassifikation

DFG Fachgebiet:
Werkstofftechnik

DDC Sachgruppe:
Technik