investigation of microstructure, and dry sliding wear of hardfaced layers produced by fcaw using cored wire fe-b-c-ti alloy

In this study, the microstructure, hardness, and dry sliding wear behavior of the hardfaced layers made by a cored wire febcti alloy were investigated. st37 steel was used as the substrate and the deposition of the hardfaced layers was conducted by the flux cored arc welding (fcaw) process under single, two, and threepass conditions. dry sliding wear tests were performed by a pinondisk apparatus, based on astmg99, at room temperature (250c) at the normal applied loads of 50, 100, and 150 n with a constant speed of 0.08 m/s for a sliding distance of 1000 m. the microstructural and phase analyses were carried out by field emission scanning electron microscopy (fesem) and xray diffraction (xrd), respectively. the results showed that the hardfaced layer produced by the singlepass process contains tic rectangular phase distributed within a matrix containing ferrite and the eutectic of ( alpha;fe2b). but, the hardfaced layers produced by the two and threepass process contain tib2 hexagonal phase in addition to tic, which prevents the formation of detrimental feb phase around fe2b and reduces the number of microcracks. moreover, the sample hardfaced by the threepass process had the best wear resistance due to the greater hardness resulted from the higher amounts of tic and tib2 phases. in addition, increasing the number of passes has led to the reduction of wear rate at all the three applied loads. at the applied load of 100 n, the wear mechanism for the all three hardfaced samples was an oxidation wear. however, at the applied load of 150 n, the wear mechanism was a combination of oxidation and delamination.