Investigation of mechanical and microstructural properties S 235 JR (ST 37-2) steels welded joints with FCAW SONMEZ, U., CEYHUN, V. vol. 52 (2014), no. 1, pp. 57 - 63 DOI: 10.4149/km_2014_1_57
Abstract Ship building industry has been growing and the industry struggling to meet the building and repairing needs. Ship building sector has started using flux cored arc welding technique that removes the negative effects of coated electrode and submerged arc welding techniques and has the superior properties of the gas metal arc welding technique regularly. In this study, S235 JR (St 37-2) steel plates with 10 mm thickness have been welded 60° and butt welded on PA, PF and PE welding positions, in a CO2 protective environment, with E71 T-1 rutile based wire electrode, and heat between increments kept stable. Hardness, tensile test, Charpy V-notch impact test, radiographic investigations, and lastly microscopic investigations were conducted in order to define the strength and microscopic properties of the weldments. As a result of these investigations, tensile strength and impact test results have been obtained for different welding positions. Hardness values were between limits set by IIW. According to the radiographic tests, for specimens welded on PE welding positions, the porosity is observed. Weld metal has been seen to have Widmannstaetten interior structure as a result of the fast cooling down on PF and PE positioned weldments, as seen on micrographs. Regions made of this interior structure were seen to be hard and brittle. Key words Flux Cored Arc Welding (FCAW), microstructure, toughness Full text (552 KB)
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