Experimental and numerical study of combined high and low cycle fatigue performance of low alloy steel and engineering application

0559519 - ÚTAM 2023 RIV CH eng J - Journal Article
Tang, Zhanzhan - Chen, Z. - He, Z. - Hu, X. - Xue, H.-Y. - Zhuge, H.
Experimental and numerical study of combined high and low cycle fatigue performance of low alloy steel and engineering application.
Materials. Roč. 14, č. 12 (2021), č. článku 3395. E-ISSN 1996-1944
Institutional support: RVO:68378297
Keywords : low alloy steel * material experiment * combined high and low cycle fatigue * high cycle fatigue * low cycle fatigue * structural performance
OECD category: Civil engineering
Impact factor: 3.748, year: 2021
Method of publishing: Open access
https://doi.org/10.3390/ma14123395

The fatigue behaviors of metals are different under different in-service environment and loading conditions. This study was devoted to investigating the combined effects of high and low cycle fatigue loads on the performance of the low alloy steel Q345. Three kinds of experiments were carried out, including the pure high cycle fatigue (HCF) tests, the pure low cycle fatigue (LCF) tests, and the combined high and low cycle fatigue (HLCF) tests. The prediction formulae were proposed for the combined high and low cycle fatigue failure. Scanning electron microscopy (SEM) and stereo microscope were used to analyze the microstructure and fracture morphology due to different fatigue loads. Case study on the combined high and low cycle fatigue damage of a steel arch bridge was carried out based on the FE method and the proposed formula. The results show that the LCF life decreases evidently due to the prior HCF damages. The HLCF fracture surface is relatively flat near the crack initiation side, and rugged at the other half part. The fatigue damages at the bridge joints increase significantly with consideration of the pre-fatigue damages caused by traffic load. In the 100th anniversary of service, the fatigue damage index without considering the HCF pre-damage is only about 50% of the coupled damage value.
Permanent Link: https://hdl.handle.net/11104/0332792