Lüders Band Propagation Monitoring in Railway Steels

Abstract

The tensile failure behavior of railway wheelset materials was studied with the aid of infrared thermography technology. The tensile specimens were prepared from the actual railway vehicle parts, which were used for over 20 years. Generally, the Lüders bands are appeared and observed in annealed soft steel like low-carbon steel, during yield point phenomenon due to the unbalance of strain. During the tensile testing, a high-speed infrared camera was employed to monitor surface temperature changes in specimen. During the tensile testing, the formation of Lüders bands was clearly observed. Moreover, the propagation of bands along the 45 degree direction of loading axis was also observed. In this investigation, the yield point phenomenon with Lüders band in railway wheelset materials was introduced, and the interpretation of tensile behavior was also discussed.