Degradation of rail-steel structure and properties of the surface layer
- Authors: Ivanov Y.F.1,2, Morozov K.V.3, Peregudov O.A.3, Gromov V.E.3
-
Affiliations:
- Institute of High-Power Electronics, Siberian Branch
- Tomsk Polytechnic University
- Siberian State Industrial University
- Issue: Vol 46, No 8 (2016)
- Pages: 567-570
- Section: Article
- URL: https://journals.rcsi.science/0967-0912/article/view/178934
- DOI: https://doi.org/10.3103/S0967091216080088
- ID: 178934
Cite item
Abstract
The change in the structure–phase states and defect substructure of the rail surface after prolonged operation (passed tonnage of 500 and 1000 million t) is studied by optical microscopy, by scanning and transmission electron diffraction microscopy, and by measurement of the microhardness and tribological characteristics. It is found that the wear rate increases by a factor of 3.0 and 3.4 after passed tonnage of 500 and 1000 million t, respectively, while the frictional coefficient is reduced by a factor of 1.4 and 1.1, respectively. After 500 million t, the cementite plates break down completely, and rounded cementite particles (10–50 nm) are formed. After 1000 million t, the initial stage of dynamic recrystallization is noted. Possible explanations of the observations are discussed. Two competing processes may occur in rail operation: (1) fragmentation of the cementite particles, with their subsequent entrainment in the ferrite grains or plates (in the pearlite structure); (2) fragmentation and subsequent solution of the cementite particles, with transfer of the carbon particles to dislocations (Cottrell atmospheres) and transportation of carbon atoms by dislocations within the ferrite grains (or plates), culminating in the formation of cementite nanoparticles.
About the authors
Yu. F. Ivanov
Institute of High-Power Electronics, Siberian Branch; Tomsk Polytechnic University
Author for correspondence.
Email: yufi55@mail.ru
Russian Federation, Tomsk; Tomsk
K. V. Morozov
Siberian State Industrial University
Email: yufi55@mail.ru
Russian Federation, Novokuznetsk
O. A. Peregudov
Siberian State Industrial University
Email: yufi55@mail.ru
Russian Federation, Novokuznetsk
V. E. Gromov
Siberian State Industrial University
Email: yufi55@mail.ru
Russian Federation, Novokuznetsk