Original scientific paper

Study on crack propagation of 42CrMo

W. C. Pei ; College of Mechanical Engineering, North China University of Science and Technology, Hebei, Tangshan, China
J. W. Dong ; College of Mechanical Engineering, North China University of Science and Technology, Hebei, Tangshan, China
H. C. Ji orcid.org/0000-0002-1592-6362 ; College of Mechanical Engineering, North China University of Science and Technology, Hebei, Tangshan, China; National Center for Materials Service Safety, University of Science and Technology Beijing, China
H. Y. Long ; College of Mechanical Engineering, North China University of Science and Technology, Hebei, Tangshan, China
S. F. Yang ; College of Mechanical Engineering, North China University of Science and Technology, Hebei, Tangshan, China

Abstract

For the fatigue failure of 42CrMo, the tensile test was performed on the CT specimen at different load ratios using a fatigue tensile tester. Data on the fatigue crack growth rate of the material and the crack tip factor were obtained. Scanning electron microscopy (SEM) was used to observe the microstructure and crack initiation and propagation of fractures. The crack initiation and propagation path law during fatigue crack propagation were obtained. The fatigue crack life was calculated by Paris formula, and the fatigue crack growth test and microscopic observation were compared. The propagation law and fatigue crack life of different stages of crack propagation were analyzed. The results show that the stable propagation stage of fatigue crack propagation is the key stage to determine fatigue fracture, the rate of growth is related to the stress ratio.

Keywords

42CrM o; fatigue crack life; fatigue crack propagation; stress; microstructure

Hrčak ID:

218357

URI

https://hrcak.srce.hr/218357

Publication date:

1.7.2019.

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