Multi-axial Fatigue of Head-Hardened Pearlitic and Austenitic Manganese Railway Steels: A Comparative Study
Journal article, 2020

Switches and crossings (S&Cs) in rail networks suffer from damage and deformation due to severe loading of their complex geometric shapes. This article presents a comparative study of the cyclic deformation characteristics and fatigue behavior of two typical crossing materials, namely head-hardened pearlitic steel and Hadfield manganese steel, as well as the associated microstructural changes. Both uniaxial and biaxial loadings (proportional and non-proportional) are studied. The pearlitic steel endured more cycles to failure for a given strain amplitude compared to the manganese steel. The cyclic response of manganese steel shows significant hardening whereas softening was observed for the pearlitic steel except under biaxial non-proportional loading. The microstructures developed in the two types of steels after deformation are characterized by optical (OM) and transmission electron microscopy (TEM). TEM micrographs reveal that the deformed microstructure of the pearlitic steel consists of threading dislocations and dislocation tangles in the ferrite lamellae. The microstructures in the manganese steel after the different loadings are composed of dislocation cells with dislocation tangles inside, intersected by straight stacking fault lamellae. The observed microstructures are related to the results of the mechanical test, and the suitability of the steels for use in S&Cs is discussed.

Author

S. Dhar

Technical University of Denmark (DTU)

Johan Ahlström

Chalmers, Industrial and Materials Science, Engineering Materials

X. Zhang

Technical University of Denmark (DTU)

H. K. Danielsen

Technical University of Denmark (DTU)

D. Juul Jensen

Technical University of Denmark (DTU)

Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science

1073-5623 (ISSN)

Vol. 51 11 5639-5652

Subject Categories

Applied Mechanics

Other Materials Engineering

Metallurgy and Metallic Materials

DOI

10.1007/s11661-020-05941-8

More information

Latest update

3/23/2021