Microstructure and Mechanical Characterization of Post Weld Heat Treated Thermite Welded Rails

Abstract

The aim of the present work was to analyze to effect of heat treatment with the properties of their thermite welded rails. The chemical composition of Rail steel was ascertained with the help of Baird emission spectrometer Two rail ends were kept 20mm apart with proper alignment and Pre-heated the rail ends (to about 1000°C) was required to help the poured molten metal in washing away the surface oxidation on the rail ends, as otherwise, the molten metal may chill and solidify immediately on coming in contact with cold rail ends, without washing off the surface oxidation.. In this process, the highly exothermic reaction between aluminum and iron oxides results in the production of molten steel which is poured into a mould around the gap to be welded. (Thermite welding was carried out.). Thermite welded rail steels were subjected to ultrasonic test to check the soundness of the weld. The heat treatment involved annealing was carried out at 820°C for 45 min and air cooling to room temperature (normalized condition). The specimens were cut in the transverse direction from Heat treated Thermite Welded Rails and prepared according to AWS D 1.1 standard. Specimens were subjected to tensile test, Impact test and results were tabulated and Microstructural analysis was carried out with the help of SEM.