Effect of strain gradient on the microstructure and mechanical properties of pearlitic steel
Paper in proceedings, 2019

Pearlitic steels, with a combination of good strength and wear properties, are commonly used for railway rails. The passage of trains creates large shear strain gradients in the surface layer of rails. Knowledge of the microstructural evolution and material properties as related to the shear strain in this layer is therefore important for prediction both of crack evolution and fatigue life. A bi-axial torsion-compression machine was used to deform fully pearlitic R260 rail steel test bars to create a similar gradient structure. Uniaxial tension and compression tests were performed on these pre-deformed test bars to evaluate the mechanical properties of the material. The local microstructural parameters, such as thickness of the ferrite and cementite lamellae, the dislocation density in the ferrite lamellae, the interlamellar spacing and eth local hardness at different places across the diameter of the bars, as well as microstructural evolution across the radius, were characterized. An attempt to set up a correlation between the local microstructural parameters, hardness and the macro mechanical properties is made and discussed in the present study.

Author

Johan Ahlström

Chalmers, Industrial and Materials Science, Engineering Materials

X. Zhang

Technical University of Denmark (DTU)

IOP Conference Series: Materials Science and Engineering

17578981 (ISSN) 1757899X (eISSN)

Vol. 580 1 012027

40th Riso International Symposium on Materials Science: Metal Microstructures in 2D, 3D and 4D
Copenhagen, Denmark,

Subject Categories

Manufacturing, Surface and Joining Technology

Other Materials Engineering

Composite Science and Engineering

DOI

10.1088/1757-899X/580/1/012027

More information

Latest update

2/3/2020 1