33. Savetovanje sa međunarodnim učešćem Zavarivanje 2024, (p. S6.2)
AUTHOR(S) / АУТОР(И): Zeljko Potkonjak, Murali Kumar, Fiazal Hussain, Rinshad Rahiman
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DOI: 10.46793/Zavarivanje24.S6.2P
ABSTRACT / САЖЕТАК:
Super-dupleks čelici su našli široku primenu u zahtevnim oblastima kao što su offšhore naftna postrojenja, hemijska i petrohemijska industrija zbog njihove izuzetne otpornosti na piting koroziju kao i odličnih mehaničkih osobina. Medjutim, zavarivanje superdupleks čelika predstavlja značajan izazov, posebno vezano za ispunjavanje kriterijuma prihvatljivosti otpornosti na piting koroziju prilikom kvalifikacije procedura. Ovaj rad obrađuje uticaj tri razlicite kombinacije purging gasova (100% Ar, 98% , Ar + 2% N2, 100% N2), na otpornost zavarenog spoja prema piting koroziji.
Zavareni uzorci su podvrgnuti testiranju na piting koroziju prema standardu ASTM G48 – A Metod, 24 sata na temperaturama 35°C i 40°C koristeći kriterijum prihvatljivosti maksimalnog dozvoljenog gubitka težine od 4 gr/m2. Rezultati su pokazali da samo 100% N2 purging gas postiže zadovoljavajuće rezultate u pogledu gubitka mase na 40°C. Analiza mikrostrukture nije pokazala nikakve vidljive strukturne anomalije u smislu formiranja neželjenih intermetalnih faza.
Studija je pokazala da se korišćenjem 100% N2 purging gasa značajno poboljšava otpornost na piting koroziju super-dupleks cevnih zavarenih spojeva uz istovremeno značajno smanjenje troškova proizvodnje.
KEYWORDS / КЉУЧНЕ РЕЧИ:
Super-dupleks čelik, piting korozija, gubitak težine, purging gas
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