The effect of shielding-gas compositions on the microstructure and mechanical properties of stainless steel weldments

Evaluation of the Shielding Gas Influence on the Weldability of Ferritic Stainless Steel

“…Figures 1 and 2 graphically shows the changes in the percentage of carbon in the metal deposit according to the shielding gas used respectively to ER430Ti and ER430LNb. It can be noticed that with the increase in the CO 2 gas content there was a proportional increase in carbon in the weld bead, fact also observed by Lundvist (1980) and by Liao & Chen (1998). It is worth noting that with the ER430LNb wire the carbon presence was significantly larger (0.094% for 8% of CO 2 content, for instance).…”

“…Gülenç et al (2005) studied GMA welding of 304L stainless steel samples and observed that the toughness of the weld beads increases with rising Hydrogen amount added to argon and with increase in the welding current level. Liao & Chen (1998) examined how the miscrostructure and mechanical properties of 304 stainless steel welds are influenced by mixtures of carbon dioxide (2 to 20%) in argon. They detected that spattering increases, notch toughness is affected by the delta-ferrite amount and oxidation potential, specially at room temperature with increase in the CO 2 content.…”

Characterization of microstructure, chemical composition, and toughness of a multipass welded joint of austenitic stainless steel AISI316L

“…Being one of the most significant parameters during the welding treatment, shielding gas protects weld metal from the adverse effects of the nitrogen and oxygen contained in the atmosphere and ensures steady arc and uniform metal transfer. Therefore, type and composition of the gas used considerably affect the microstructure and mechanical characteristics of the joined material [10][11][12][13][14][15][16][17][18].…”

“…High arc energy given by CO 2 gas provides a higher melting speed and satisfactory penetration based on other shielding gas types. Moreover, its oxidative effect in welding arc plasma results in oxidation of the elements contained in the stainless steel such as Mn, Si, Al, Cr, and Ti [11][12][13][14]16]. Some studies have reported that this situation was reported to have a higher amount of inclusion content compared to the alkaline-based additional weld metals due to the fact that it causes inclusion formation in weld metal and the rutile-based additional weld metals have low purification capability [16,19].…”

“…Arivazhagan et al [16] joined modified 9Cr-1Mo material by using the FCAW method and examined the effect of shielding gas, mixed of Ar and CO 2 , on mechanical properties, and they determined that as the CO 2 amount contained in the mixture rate increased, the amount of oxygen contained in dissolved weld metal increased and also the mechanical values decreased and the inclusion amount contained in weld metal increased. It has been shown in numerous studies that it affects composition of the shielding gas used in welding treatment and microstructure and consequently mechanical properties of materials joined as multipass [8,[12][13][14][15][16]21]. However, characterization of the microstructural transformations occurred and the inclusions in oxide form and also their effect on mechanical values were not studied in detail.…”