Technical Reports

Fatigue Behavior of AAR Class A Railroad Wheel Steel at Ambient and Elevated Temperatures

  • 01
  • Dec
  • 2006
AUTHOR: Fraser J. McMaster and Guadalupe B. Robledo
KEYWORDS: Class A wheel steel, S-N fatigue testing, railroad wheels, fatigue specimens, loading conditions, stop-braking, tensile strength, Sines parameters
ABSTRACT: This report documents a test program to determine the material properties (chemical composition, tensile, and fatigue) at ambient and elevated temperatures of a Class A wheel steel as designated by the Association of American Railroads. The 3 temperatures examined included ambient room temperature, 500 °F, and 1000 °F. The fatigue properties determined at ambient temperature are required to address rail vehicle wheels equipped with disc brakes, which are not exposed to frictional heating during stop-braking. Researchers performed fatigue testing to determine the S-N curves at each of the three temperatures. Furthermore, the research team performed a large number of fatigue tests at R-ratios of -1.0 and 0.05 for each of the test temperatures to enable reliable estimates of the Sines parameters, A and α.