Comparison of pulsed and continuous current gas tungsten arc welding in dissimilar welding between UNS S32750 and AISI 321 in optimized condition
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In this research, mechanical and corrosion properties of dissimilar joint between duplex stainless steel UNS S32750 duplex stainless steel and AISI 321 austenite stainless steel welded by pulsed current gas tungsten arc welding (PCGTAW) and continuous current gas tungsten arc welding (CCGTAW) were compared. The welding parameters and the filler metal were the same in both methods. Microstructural characterization of joint was determined by optical and scanning electron microscope. The pitting potential was evaluated by potentiodynamic polarization test in 3.5 wt.% NaCl solution at room temperature. Mechanical properties of optimal joint were investigated by impact test and vickers microhardness. Microstructural evaluation shows that the equal amounts of ferrite and austenite were obtained in PCGTAW weldment, while in CCGTAW weldment fraction of phases changed to 40% ferrite and 60% austenite. TiN precipitations were formed in fusion line of CCGTAW weldment on the side of AISI 321 austenite stainless steel. The average values of hardness in PCGTAW and CCGTAW weld zone were 241 and 225 HV0.2, respectively. The higher amount of ferrite in PCGTAW weldment in comparison with CCGTAW weldment was the reason of higher hardness average. The toughness of PCGTAW and CCGTAW was 106 and 102 J, respectively. Based on cyclic polarization test, pitting potential of weldment welded with PCGTAW and CCGTAW was 1.03 and 0.8 V, respectively, which is a proof of better pitting corrosion resistance of the weld zone in PCGTAW method.
KeywordsAustenic stainless steel Super duplex stainless steel PCGTAW CCGTAW Dissimilar welding Corrosion behavior Mechanical properties
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- 10.Ramkumar KD, Chandrasekhar A, Srivastava A, Preyas H, Chandra S, Dev S, Arivazhagan N (2016) Effects of filler metals on the segregation, mechanical properties and hot corrosion behaviour of pulsed current gas tungsten arc welded super-austenitic stainless steel. J Manuf Process 24:46–61CrossRefGoogle Scholar
- 14.Abdollahi A, Shamanian M, Golozar MA (2018) Parametric optimization of pulsed current gas arc welding of dissimilar welding between UNS32750 and AISI 321 based on Taguchi method. Trans Indian Inst Metals 71(3):597–603Google Scholar
- 15.Atlas Steels Australia, Stainless Steel - Grade 310 (UNSS31000) http://www.azom.com/article.aspx?ArticleID=966.
- 16.Outokumpu Stainless A (2013) Handbook of stainless steel. Outokumpu Stainless AB, AvestaGoogle Scholar
- 19.ASTM E (2007) Standard test methods for notched bar impact testing of metallic materials. E23-07a, Pennsylvania, PA, USAGoogle Scholar
- 20.ASTM G (2003) “48-03.” Pitting and crevice corrosion resistance of stainless steels, USAGoogle Scholar
- 23.Kotecki D, Lippold J (2005) Welding metallurgy and weldability of stainless steels. Wiley, HobokenGoogle Scholar