Guidelines for the rail grade selection
M. Tomicic-Torlakovic, University of Belgrade, Faculty of Civil Engineering, Belgrade, Serbia Over the years the rail steel manufacturing process and quality of material produced have improved significantly through alloy design and/or head treatment procedure. The objective of this paper is to give the recommendations for the application of the available rail steel grades in accordance with the accessible investigations. The main source are the results of the Innotrack project in correlation with Euronorm prEN 13674-1. The conclusion for the Serbian Railway is made.
Materials Developments in the Australian Railway Industry - Past, Present and Future
This paper provides an overview of the considerable material developments which have and are occurring within the railway industry. The performance of components has been enhanced not only by improvements in the materials used but also by modification of designs and by improved manufacturing procedures. Possible future areas of development are also discussed. It is concluded that the currently available range of materials and designs, together with the appropriate management procedures allow systems to choose components on a more rational, economic basis.
PRODUCTION AND PROPERTIES OF HIGH-SERVICEABILITY RAIL
In order to improve the serviceablity of rails, the service life of a rail was divided into several elementary processes and the requisites for every process were investigated. The results of this study proved that increasing the strength of rails through pearlite refining, austenite grain refining, and preservation of compressive residual stress was effective in improving rail serviceability. High strength and a fine pearlitic microstructure increase the wear resistance of rails and deter the initiation of contact fatigue cracking on the surface of rails. Compressive residual stress delays fatigue crack propagation. One type of rail that satisfies these requirements is head-hardened rail. The head of these rails is slack quenched by blown air after austenitizing to cause the isothermal pearlite transformation. The hardened zone of this rail has a yield stress and tensile strength that exceed 800 MPa and 1200 MPa, respectively, and very fine pearlitic microstructure. This head-hardened rail also has a compressive residual stress of about 400 MPa on the running surface and on the sides of rail head. It has also been confirmed that this rail performs will in heavy-load railways. (Author)