Investigation of the usability of blast furnace slags in the production of rutile type

In this thesis study, the usability of blast furnace slag as a flux in the electrode cover in the production of rutile-type covered electrodes was investigated. In this context, rutile-type covered electrodes were produced by the mold-pressing method. It was carried out by single pass welding on the AISI 1020 steel plate by electric arc welding method using the produced covered electrodes. In welding tests, 80A current and electrode positive pole were preferred. The produced electrodes were primarily evaluated based on performance criteria. The electrodes that received positive results from the performance criteria were then characterized by subjecting them to microstructure, hardness, chemical composition, and tensile tests in compliance with commercial manufacturers and relevant standards. When the results were evaluated, it was determined that the slag formed after welding was partially porous, the weld metal was shiny, non-porous, and smooth, and the stability of the arc during welding was sufficient. It has been determined that the microstructures of the coated electrodes containing blast furnace slag produced consist of ferrite and pearlite phase/phase mixture, as expected, and that the microstructures are oriented towards the welding direction. As for the hardness test results, results were obtained in the range of 180-190 HV. The yield, tensile, and percent elongation results obtained from the tensile test results and the results of the commercial market and standards gave largely parallel results. As a result, the usability of blast furnace slag as a flux in coated electrode production has been demonstrated in this thesis study.