Karakterizacija zvarnega spoja pri podvodnem obločnem varjenju

Primožič, Špela (author), Klobčar, Damjan (mentor)

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.

• Language: Slovenian
• Keywords: mokro podvodno obločno varjenje, zvarni spoj, karakterizacija zvarov, mehanske lastnosti zvarov, trdota poroznost
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [Š. Primožič]
• Year: 2026
• Number of pages: XI, 50 f.
• PID: 20.500.12556/RUL-183802
• UDC: 621.791.053:539.53(043.2)
• COBISS.SI-ID: 282660611
• Publication date in RUL: 19.06.2026

Secondary language

• Language: English
• Title: Characterization of a weld joint in underwater arc welding

Abstract

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.

• Keywords: wet underwater arc welding, welded joint, weld characterization, mechanical properties of welds, hardness, porosity