Experimental and computational study on microstructural evolution in 2205 duplex stainless steel during high temperature aging

Evolution of microstructure and corrosion behavior in 2205 duplex stainless steel GTA-welding joint

“…Much literature has investigated the corrosion resistance of 2205 DSS weld joint was dramatically decreased due to the coarser grain size, higher ferrite contents and more extensive precipitation of chromium nitride than the base metal [21][22][23][24][25][26][27]. As mentioned above, zone 2 has the poorest corrosion resistance and this owes to two aspects.…”

An Experimental and Numerical Approach for the Welding Effects on the Duplex Stainless Steel Microstructure

“…However, DSS are frequently submitted to welding operations and, depending on the thermal history undergone by the material during this procedure, the precipitation of brittle intermetallic phases such as sigma (σ) and chi(χ) [3][4][5][6][7][8][9] may occur besides of impairing the adequate balance between the fractions of the ferrite and austenite phases at the heat affected zone (HAZ). In terms of secondary phases, the sigma phase is the most important intermetallic compound that could precipitate, since it has a deleterious influence on the mechanical properties and corrosion resistance of the DSS and higher volumetric fraction observed among all them [10][11][12][13][14][15][16] . In fact, some works [11][12][13][17][18][19][20][21] have shown that the impact toughness and corrosion resistance of the DSS drastically decrease even in the presence of very low amounts of sigma phase.…”

“…In terms of secondary phases, the sigma phase is the most important intermetallic compound that could precipitate, since it has a deleterious influence on the mechanical properties and corrosion resistance of the DSS and higher volumetric fraction observed among all them [10][11][12][13][14][15][16] . In fact, some works [11][12][13][17][18][19][20][21] have shown that the impact toughness and corrosion resistance of the DSS drastically decrease even in the presence of very low amounts of sigma phase. Sigma phase is a hard, brittle and non-magnetic intermetallic phase with a tetragonal crystalline structure being formed basically by elements Fe, Cr and Mo 3,10,14 and usually forms after long holding times at temperatures between 650 and 950 °C and after cooling from high temperatures, as those occurring at the DSS HAZ during welding 22 .…”

Coarsening of carbides during different heat treatment conditions

“…Studies have shown that precipitation strengthening effect of small carbides can significantly improve the mechanical properties of steel [2][3][4]. In recent years, coarsening of carbides are widely studied experimentally and through thermodynamic and kinetic calculations [5][6][7][8][9]. The precipitation behavior of carbides after different aging time was investigated by using carbon replica and TEM technique which greatly improved the accuracy of size measurement [10,11].…”