Effect of shielding gas in laser welding of austenitic stainless steel

Zaključna naloga obravnava preverjanje vpliva zaščitnega plina pri laserskem varjenju avstenitnega nerjavnega jekla. Glavni razlog je pocenitev proizvodnega procesa z uporabo cenejšega zaščitnega plina dušika namesto argona. Kakovost izdelanih zvarov smo testirali vizualno, s tlačno-strižnim preizkusom in z metalografsko analizo. Ugotovili smo, da je zaščitni plin dušik dobra alternativa argonu. Po vizualni kontroli smo ugotovili, da nastane lep zvar, s tlačno-strižnim preizkusom smo dokazali, da lahko tak var zdrži obremenitve v uporabi, z metalografsko analizo pa smo pokazali, da nam tako definiran postopek zagotavlja zahtevano globino zavaritve.The final thesis discusses the influence of shielding gasses during laser welding of austenitic stainless steel. The main reason for conducting this research is the reduction of the production process costs, using a cheaper shielding gas nitrogen instead of argon. The quality of welds was tested using visually, with a pressure-shear testing and metallographic analysis. It was found that shielding gas nitrogen is a good alternative to argon. Visual inspection proved the quality of weld appearance. Pressure-shear test we proved the mechanical strength of the weld and metallographic analysis sufficient penetration depth. It was concluded that argon shielding gas can be exchanged with nitrogen at laser welding of austenitic stainless steel