Hydrogen behavior in SAF 2205 duplex stainless steel

In Situ Synchrotron Radiation Measurements During Axial Strain In Hydrogen Cathodically Charged Duplex Stainless Steel SAF 2205

“…According with Glowacka et al 13,14 , the hydrogen charging can induce the formation of martensite ε or α'. Nevertheless, Silverstein et al 24 pointed out that the hydrogen traps of higher energy (residual hydrogen) such as high angle boundaries, vacancy, austenite-ferrite interface and clusters are related to the transformation from austenite to martensite during hydrogen charging; while the hydrogen traps of low energy such (diffusible hydrogen) such as elastic stress field of dislocations, screw's dislocation core or grain boundaries do not have a significant influence in the hydrogen-induced phase transformations. In second place, hydrogen decreased the martensite formation during axial strain.…”

Hydrogen Distribution in a Duplex Stainless Steel Investigated by Means of Hydrogen Microprint Technique

“…[18][19][20] The hydrogen atoms in steels have been roughly divided into two categories: one is non-diffusive hydrogen atom strongly trapped by stable trapping sites such as precipitates and inclusions, and the other is diffusive hydrogen atom that are in the interstitial site of the matrix or lightly trapped by less stable sites such as dislocations and grain boundaries. [21][22][23][24][25] The most important issue is the behaviour of diffusive hydrogen in the microstructure that affects the failure: whether it is in the interstitial lattice site or lightly trapped by some lattice defects, and where the diffusion path is. Acquiring such information is extremely difficult by common analysing technique such as scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDXS), since hydrogen is small in quantity and its X-ray cannot be detected.…”

“…[4][5][6] These combination lead to a degradation of mechanical properties and delayed fracture, known as hydrogen embrittlement (HE). [7][8][9] According to the authors, previous research, 6,7) the main cause of the fracture in the case of HE in DSS is closely related to the microstructure composed of the co-existing two phases (ferrite and austenite), combined with the local stress state in the material. Hydrogen diffusion in the ferrite proceeds much faster than in the austenite, despite the lower solubility than in the austenite.…”

Коррозионное растрескивание под напряжением металлов и сплавов в агрессивных H-=SUB=-2-=/SUB=-S-CO-=SUB=-2-=/SUB=--Cl-=SUP=---=/SUP=- средах

“…Коррозионное поведение, в том числе и питтинговая коррозия дуплексных сталей зависят от термообработки, микроструктуры, степени легирования, степени деформации [42][43][44][45][46][47][48] и т. д. Дуплексные стали отжигаются в области температур 600−1200 • C; во время отжига меняется соотношение α : γ-фаз и, кроме того, фазы обогащаются разными элементами. Cr и Mo обогащают ферритную α-фазу, а Ni, Mn и N -аустенитную γ-фазу, что сказывается как на общую, так и на локализованную коррозию [49].…”

“…Дуплексные стали используются преимущественно в случае, когда требуется противодействовать воздействию водорода в нагруженном состоянии. По этой причине большое значение придается выяснению влиянию водорода на механические свойства этих сталей [46,54], определению мест локализации (ловушек) водорода, величины связи водорода с ловушками, кинетики разрушения стали вследствие водородного охрупчивания [54].…”