The rail modal plays an important role in the economy, mainly contributing to freight transport. Rail tracks are subject to defects from manufacturing to defects originating in service. The prevention of rail failures is one of the main objectives to keep the railway safe. In this work, a railroad track that presented the canoeingin defect in the rail head region, located in a spark-welded joint. Therefore, the objective of this work was to evaluate the canoeingin defect resulting from the spark welding identified in the railway tracks. The rail classified as TR-68 was subjected to chemical, mechanical and metallographic characterizations. The chemical composition analysis was performed using an optical emission spectrometer, macro and microstructural evaluation of the rail track was carried out using a stereoscope and optical microscope, respectively. In addition, Rockwell hardness and Vickers microhardness tests were performed. The welded joint showed little significant changes in the dispersion of alloy elements, the chemical composition was in agreement with the literature. The macrostructural analysis found a defect (crack) in the rail head and decarburization of the central line of the weld bead, where the canoeing defect occurred. In the microstructural analysis, the pearlitic morphology of the material was found, as well as proeutectoid cementite in the central line of the weld bead. Hardness and microhardness tests revealed a sharp drop in hardness in the heat-affected zone (HAZ) and in the central line (LC), where the defect occurred. The rail characterized did not present deformations in the microstructure of the billet surface, being a new rail that possibly failed and failed the stage of welding in shipyard and rejected for application in service.
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