Portal de Periódicos da CAPES

Characterization of used and virgin pearlitic rail steel

2020; Elsevier BV; Volume: 39; Linguagem: Inglês

10.1016/j.matpr.2020.07.718

2214-7853

Gandham Bhavani, Jay Prakash Srivastava, V. Mahesh,

Mechanical stress and fatigue analysis

Rail transport system experience complex loading conditions that alters the microstructure of wheel and rail material near the contact interface region. This paper presents microstructure and hardness study of virgin and used pearlitic rail steel. Samples are prepared from the railhead section taken from nearby Kazipet Railway Division, (South Central Railway). The microstructure and hardness variation along the depth from the surface is presented. In continuation to the author's previous study [1], along the transverse direction, this time samples are taken in a longitudinal direction. Microstructural observations show the existence of pro-eutectoid ferrite at the grain boundaries for the sample near to the rail surface. Presence of this softer material favours micro-crack initiation causing wear debris formation and rolling contact fatigue defects. Hardness test results reveal an increase in hardness values for material points close to the surface, while base material hardness remains almost the same. Higher hardness values at the surface level are indicating the formation of a brittle material which is more susceptible to crack initiation and propagation. This experimental investigation enriches knowledge domain in the formation of rolling contact fatigue defects. This will help railway engineers to schedule proper maintenance planning and material scientists to develop superior rail material.