Sigma phase precipitation in duplex stainless steel 2205

Sieurin, Henrik; Sandström, Rolf

doi:10.1016/j.msea.2006.08.107

Cited by 279 publications

(175 citation statements)

References 17 publications

Supporting

Mentioning

154

Contrasting

Unclassified

Order By: Relevance

“…At about 936 °C begins to precipitate the intermetallic σ phase, which ends for the analyzed chemical composition of about 510 °C. This range of temperature generally correspond to literature value [13,14], a little too low is the temperature 510°C. According to the data obtained in the FactSage for the equilibrium conditions there are no other intermetallic phases.…”

Section: Research Results and Their Discussionsupporting

confidence: 88%

“…Results obtained in the micro fractography analysis of cracks are shown in Figures 4 and 5. The microstructure analysis showed, next to the primary phase of ferrite and austenite, presence of the sigma phase, which negative interaction is generally known [13,14]. In the tested material were found two types of sigma phase precipitates in the form of single precipitates or a single colony in ferrite and in the form of a thin, more or less continuous film on the border of ferrite -austenite.…”

Section: Research Results and Their Discussionmentioning

confidence: 85%

See 1 more Smart Citation

The Cracking Mechanism of Ferritic-Austenitic Cast Steel

Stradomski

2016

Archives of Foundry Engineering

View full text Add to dashboard Cite

In the high-alloy, ferritic -austenitic (duplex) stainless steels high tendency to cracking, mainly hot-is induced by micro segregation processes and change of crystallization mechanism in its final stage. The article is a continuation of the problems presented in earlier papers [1 -4]. In the range of high temperature cracking appear one mechanism a decohesion -intergranular however, depending on the chemical composition of the steel, various structural factors decide of the occurrence of hot cracking. The low-carbon and low-alloy cast steel casting hot cracking cause are type II sulphide, in high carbon tool cast steel secondary cementite mesh and / or ledeburite segregated at the grain solidified grains boundaries, in the case of Hadfield steel phosphorus -carbide eutectic, which carrier is iron-manganese and low solubility of phosphorus in high manganese matrix. In duplex cast steel the additional factor increasing the risk of cracking it is very "rich" chemical composition and related with it processes of precipitation of many secondary phases.

show abstract

Section: Research Results and Their Discussionsupporting

confidence: 88%

Section: Research Results and Their Discussionmentioning

confidence: 85%

The Cracking Mechanism of Ferritic-Austenitic Cast Steel

Stradomski

2016

Archives of Foundry Engineering

View full text Add to dashboard Cite

show abstract

“…However, in situations where the components or structures are subjected to prolonged service at higher temperatures or thermal cycling, these steels are prone to the formation of additional phases [1,4], which often degrade the physical, chemical and mechanical properties [4], e.g. the formation of sigma phase during the thermal ageing of duplex steels under a range of conditions [2][3][4][5]. It is associated with embrittlement [1,4,5] and loss of corrosion resistance [4,5], and as such can be severely damaging to the overall structural integrity of a component fabricated from these steels.…”

Section: Introductionmentioning

confidence: 99%

“…the formation of sigma phase during the thermal ageing of duplex steels under a range of conditions [2][3][4][5]. It is associated with embrittlement [1,4,5] and loss of corrosion resistance [4,5], and as such can be severely damaging to the overall structural integrity of a component fabricated from these steels.…”

Section: Introductionmentioning

confidence: 99%

Quantification of sigma-phase evolution in thermally aged 2205 duplex stainless steel

et al. 2015

View full text Add to dashboard Cite

In this study, the evolution of sigma-phase development in a 2205 duplex steel was studied following thermal ageing in the temperature range 750-850°C for periods up to 100 h. A suite of materials analysis techniques including combined electron backscatter diffraction-energy-dispersive X-ray imaging and magnetic force microscopy are used to quantify the change in volume fraction of the phases. The experimental results for each ageing condition are compared with the results from other ageing experiments and the predictions from the computer modelling. They show good correlation for the amount of sigma phase formed under a range of ageing conditions (and thus varying quantities of sigma phase). EBSD measurements showed no preferential orientation relationships relative to the parent ferrite for the nucleation of sigma phase, implying that the minimisation of boundary misorientation energy is not significant in determining sigma-phase nucleation sites. The results are discussed with respect to the experimentally measured properties of sigma phase and the kinetics of the precipitation process.

show abstract

“…Since σ is the intermetallic phase more prominently formed during field applications of duplex stainless steel, its formation has been the object of several studies throughout the years, mostly focused on morphology and formation kinetics [1][2][3][4][5][6][7][8] , as well as its effects on mechanical properties [9][10][11] and corrosion resistance [12][13][14][15][16][17] . Processes that include high temperature thermal cycling, such as welding, are particularly critical regarding the appearance of σ, due to the temperature range to which the heat affected zone is exposed in a poorly controlled manner.…”

Section: Introductionmentioning

confidence: 99%

Use of Magnetic Barkhausen Noise (MBN) to Follow Up the Formation of Sigma Phase in Saf2205 (UNS S31803) Duplex Stainless Steel

et al. 2016

View full text Add to dashboard Cite

Duplex stainless steels have a structure normally composed of austenite and ferrite in approximately equal proportions. In order to attain control of its fabrication processes and performance, it is important to understand its microstructural evolution, due to the formation of intermetallic phases such as sigma (σ) and chi (χ), which may cause a severe deterioration of mechanical properties. In the present study, the evolution of sigma phase during heat treatments at temperatures in which intermetallic phases can be formed (800ºC-900°C) was studied using magnetic analyses on a SAF2205 (DIN 1.4462/UNS S31803) steel. A significant reduction of the intensity of Magnetic Barkhausen Noise (MBN) was observed with the increase of heat treatment time, indicating a decrease in the quantity of ferromagnetic phases. For 24-hour-long treatments, the Barkhausen Noise signal is almost completely enclosed by the background noise, indicating the existence of a very small volume fraction of ferrite. If proper calibration samples are to be produced, this technique may be a viable method for non-destructive evaluation of field components working under thermal conditions that may cause the formation of intermetallic phases.

show abstract

Sigma phase precipitation in duplex stainless steel 2205

Cited by 279 publications

References 17 publications

The Cracking Mechanism of Ferritic-Austenitic Cast Steel

The Cracking Mechanism of Ferritic-Austenitic Cast Steel

Quantification of sigma-phase evolution in thermally aged 2205 duplex stainless steel

Use of Magnetic Barkhausen Noise (MBN) to Follow Up the Formation of Sigma Phase in Saf2205 (UNS S31803) Duplex Stainless Steel

Contact Info

Product

Resources

About