20.500.12556/RUL-183802 Karakterizacija zvarnega spoja pri podvodnem obločnem varjenju Characterization of a weld joint in underwater arc welding Zaključno delo obravnava karakterizacijo zvarnega spoja pri podvodnem obločnem varjenju konstrukcijskega jekla AH36. Namen raziskave je bil analizirati vpliv podvodnega okolja na mehanske lastnosti in kakovost zvarnih spojev. Eksperimentalni del je vključeval izvedbo mokrega podvodnega varjenja, pripravo preizkušancev ter izvedbo mehanskih preizkusov, kot so natezni preizkus, upogibni preizkus, preizkus udarne žilavosti in merjenje trdote. Dodatno je bila izvedena makroskopska analiza zvarnega spoja. Rezultati so pokazali, da zvarni spoji dosegajo relativno visoke vrednosti natezne trdnosti, vendar izkazujejo zmanjšano duktilnost in žilavost, kar je posledica hitrega ohlajanja in nastanka poroznosti. Trdota v toplotno vplivanem območju je lokalno presegla izbrani kriterij 320 HV10, najvišje vrednosti pa so bile izmerjene v neposredni bližini talilne meje. Raziskava potrjuje, da imajo procesni parametri in pogoji pod vodo ključen vpliv na kakovost zvarov ter da je njihova optimizacija bistvena za izboljšanje mehanskih lastnosti. Final thesis addresses the characterisation of a welded joint produced by underwater arc welding of AH36 structural steel. The aim of the research was to analyse the influence of the underwater environment on the mechanical properties and quality of welded joints. The experimental work included the execution of wet underwater welding, the preparation of test specimens, and mechanical testing, including tensile testing, bend testing, impact toughness testing, and hardness measurements. In addition, a macroscopic analysis of the welded joint was carried out. The results showed that the welded joints achieved relatively high tensile strength values; however, they exhibited reduced ductility and toughness as a consequence of rapid cooling and the formation of porosity. The hardness in the heat-affected zone locally exceeded the selected criterion of 320 HV10, with the highest values measured in the immediate vicinity of the fusion boundary. The study confirms that process parameters and underwater conditions have a significant influence on weld quality, and that their optimisation is essential for improving mechanical properties. mokro podvodno obločno varjenje zvarni spoj karakterizacija zvarov mehanske lastnosti zvarov trdota poroznost wet underwater arc welding welded joint weld characterization mechanical properties of welds hardness porosity true false false [Š. Primožič] Slovenski jezik Angleški jezik Diplomsko delo/naloga 2026-06-19 08:30:25 2026-06-19 08:30:35 2026-06-24 09:34:37 0000-00-00 00:00:00 2026 0 Ljubljana 0 XI, 50 f. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.791.053:539.53(043.2) 285725 282660611 47107.pdf 47107.pdf 1 2B6E94E44A084C275C94BBCED517C912 4f1eedb4a8186d6864e468072c06f84bcf104673dcc43fc2125b8ca2fba45ee6 531af1e1-6ba8-11f1-9b0d-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=235987 47108.png 47108.png 1 BA3A22CFB112E242B4FD1C4902B5EB23 82080b4b1b6ad54c3d2e52bcb0980ba12f8e2ff9898c216faef989f23853db84 531bc8e2-6ba8-11f1-9b0d-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=235988 47109.png 47109.png 1 90D635CABC86F036671C5F23EDA96543 cd758774905ff0ed1574c7af3d0dc4f7a0a5f12827cbfd1c4a1f247f0cc8659d 531d1a79-6ba8-11f1-9b0d-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=235989 47110.png 47110.png 1 777FF7A81B2B880E6C551A203CD39F9E ab41515231cb4368dbba432522b1b6cea8ff33abaa29ec96ac62f387d16fc2ff 531d6c1e-6ba8-11f1-9b0d-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=235990 47111.png 47111.png 1 C6986FE51A8BC921DE4CA3CE84426803 b97f5b21337f934ecebc951e00affe810f9ea61dc90bbaf733a147f6c52d0cee 531da8c3-6ba8-11f1-9b0d-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=235991 Fakulteta za strojništvo 0 0 0