Metallurgical study of rail squats

Valente, Carlos, Daniel, William J. T. and Meehan, Paul A. (2010). Metallurgical study of rail squats. In: David Bond and John Dring, CORE 2010 Conference on Railway Engineering Proceedings: Rail - rejuvenation and renaissance. CORE 2010 Conference on Railway Engineering, Wellington, New Zealand, (346-353). 12-14 December 2010.

Attached Files (Some files may be inaccessible until you login with your UQ eSpace credentials)
Name Description MIMEType Size Downloads
UQ237265_fulltext_other.pdf ERA evidence - not publicly available application/pdf 1.57MB 660
Author Valente, Carlos
Daniel, William J. T.
Meehan, Paul A.
Title of paper Metallurgical study of rail squats
Conference name CORE 2010 Conference on Railway Engineering
Conference location Wellington, New Zealand
Conference dates 12-14 December 2010
Proceedings title CORE 2010 Conference on Railway Engineering Proceedings: Rail - rejuvenation and renaissance
Place of Publication Wellington, New Zealand
Publisher Engineers Australia
Publication Year 2010
Sub-type Fully published paper
ISBN 9780908960569
9780908960552
Editor David Bond
John Dring
Start page 346
End page 353
Total pages 8
Language eng
Abstract/Summary A rail squat is a type of rolling contact fatigue defect of growing concern. A crack grows below the rail surface, leading to a depression in the rail as material above the crack flows plastically. Studies of squat cracks using optical and electron microscopy will be described. One feature often observed is a "white etching layer" on the surface of the rail. The name reflects the fact that this layer refuses to reveal its crystalline microstructure when etched with nitric acid, and indicates it has a nano-crystalline nature. It is a thin brittle layer (eg 30 microns thick) formed by severe local heating, and can occur with transient wheel slip. The presence of this layer can initiate a crack, which can then grow subsurface both in the direction of traffic and against the direction of traffic. The appearance of the crack surface will be discussed. There are regions that show evidence of cycles of faster or slower crack growth, and other smooth regions, that are featureless even when seen through a microscope. These give clues as to how the crack grew, whether in shear or in tension due to water getting in the crack.
Q-Index Code E1
Q-Index Status Provisional Code
Institutional Status UQ

Document type: Conference Paper
Collection: School of Mechanical & Mining Engineering Publications
 
Versions
Version Filter Type
Citation counts: Google Scholar Search Google Scholar
Created: Fri, 18 Mar 2011, 10:20:58 EST by Deanna Mahony on behalf of School of Mechanical and Mining Engineering