Effect of Nitrogen on Hydrogen Embrittlement of Austenitic Stainless Steels Based on Type 316LN

The effect of nitrogen on hydrogen gas embrittlement (HGE) in 1 and 70 MPa hydrogen and internal reversible hydrogen embrittlement (IRHE) of austenitic stainless steels of 17Cr11Ni2Mo(0.4 in max.)N alloys, based on type 316LN, was investigated by slow strain rate technique tests at room temperature in comparison with the effect of Ni on HGE and IRHE of Ni-added type 316 stainless-steel-alloys. For the nitrogen-added alloys, HGE and IRHE decreased with increasing nitrogen content, where α′ martensitic transformation occurred. HGE was not observed but IRHE was observed above the nitrogen content, where austenite is completely stabilized by nitrogen. Hydrogen-induced fracture related to the strain-induced α′ martensite structure was observed in HGE specimens and that together with brittle transgranular fracture was observed in IRHE specimens. HGE of the nitrogen-added alloys is larger than that of the Ni-added alloys in the Nieq range, where α′ martensitic transformation occurred. No HGE was observed in both the nitrogen-added alloys and the Ni-added alloys, but IRHE was observed in not the Ni-added alloys but the nitrogen-added alloys above the Nieq, where no martensite is identified in both alloys. It is discussed that the α′ martensite and the austenite of the nitrogen-added alloys were more sensitive to HGE or IRHE than those of the Ni-added alloys.

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Internal Reversible Hydrogen Embrittlement and Hydrogen Gas Embrittlement of Austenitic Stainless Steels Based on Type 316

Volume 6: Materials and Fabrication, Parts A and B ◽

10.1115/pvp2009-77605 ◽

2009 ◽

Author(s):

Masaaki Imade ◽

Lin Zhang ◽

Mao Wen ◽

Takashi Iijima ◽

Seiji Fukuyama ◽

...

Keyword(s):

Hydrogen Embrittlement ◽

Room Temperature ◽

Austenitic Stainless Steels ◽

Hydrogen Gas ◽

Hydrogen Transport ◽

Ni Content ◽

Hydrogen Segregation ◽

Slow Strain Rate Technique ◽

Reversible Hydrogen Embrittlement ◽

Martensite Structure

The internal reversible hydrogen embrittlement (IRHE) of austenitic Fe(10–20)Ni17Cr2Mo alloys based on type 316 stainless steel was investigated by tests using the slow strain rate technique from 80 to 300 K in comparison with its effect on the hydrogen gas embrittlement (HGE) of the alloys in hydrogen at a pressure of 1 MPa. The IRHE and HGE of the alloys in 70 MPa hydrogen at room temperature was also investigated. At low temperatures, IRHE occurred below a Ni content of 15% (Ni equivalent (Nieq):29%), increased with decreasing temperature, reached a maximum at 200 K, and decreased with further decreasing temperature, similarly to the temperature dependence of HGE. At room temperature, IRHE and HGE were observed below a Ni content of 14% (Nieq:28%) and decreased with increasing Ni content (Nieq). The dependence of HGE on hydrogen pressure increased with decreasing Ni content (Nieq). Hydrogen-induced fracture closely related to the strain-induced α′ martensite structure and twin boundaries mainly occurred for both IRHE and HGE. Dimple ruptures caused by hydrogen segregation occurred in only IRHE at 150 K. The content of strain-induced α′ martensite increased with decreasing temperature and Ni content (Nieq). Thus, the susceptibility to IRHE and HGE depended on Ni content (Nieq). It was concluded that both IRHE and HGE were controlled by the amount of strain-induced α′ martensite above 200 K, whereas they were controlled by the hydrogen transport below 200 K.

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Internal Reversible Hydrogen Embrittlement of Austenitic Stainless Steels Based on Type 316 at Low Temperatures

ISIJ International ◽

10.2355/isijinternational.52.240 ◽

2012 ◽

Vol 52 (2) ◽

pp. 240-246 ◽

Cited By ~ 20

Author(s):

Lin Zhang ◽

Masaaki Imade ◽

Bai An ◽

Mao Wen ◽

Takashi Iijima ◽

...

Keyword(s):

Hydrogen Embrittlement ◽

Stainless Steels ◽

Low Temperatures ◽

Austenitic Stainless Steels ◽

Reversible Hydrogen Embrittlement

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Hydrogen Embrittlement of Ultrafine-Grained Austenitic Stainless Steels

REVIEWS ON ADVANCED MATERIALS SCIENCE ◽

10.1515/rams-2018-0018 ◽

2018 ◽

Vol 54 (1) ◽

pp. 25-45 ◽

Cited By ~ 1

Author(s):

E. G. Astafurova ◽

S. V. Astafurov ◽

G. G. Maier ◽

V. A. Moskvina ◽

E. V. Melnikov ◽

...

Keyword(s):

Martensitic Transformation ◽

Hydrogen Embrittlement ◽

Stainless Steels ◽

Subgrain Size ◽

Austenitic Stainless Steels ◽

Mechanical Twinning ◽

Coarse Grained ◽

Flow Strength ◽

Hydrogen Charging ◽

Ultrafine Grained

Abstract The effect of electrochemical hydrogen-charging on tensile properties, mechanisms of plastic deformation and fracture micromechanisms was studied using two ultrafine-grained (UFG) Cr-Ni austenitic stainless steels. UFG austenitic structures with an average subgrain size of 200 nm for CrNiMo (316L-type) and 520 nm for CrNiTi (321-type) steel were produced using hot-to-warm ABC-pressing. Hydrogen-charging up to 100 hours weakly influences stages of plastic flow, strength properties and elongation of the UFG steels. TEM analysis testifies to hydrogen-assisted partial annihilation and rearrangement of dislocations into dislocation tangles, and to hydrogen-induced variation in ratio of low- and high-angle misorientations in UFG structure of both steels. Hydrogen-alloying promotes mechanical twinning and deformation-induced γ ® e martensitic transformation in the UFG steels under tension. Ultrafine-grained CrNiTi steel with lower stacking fault energy (SFE) is more susceptible to mechanical twinning and deformation-induced γ ® e martensitic transformation in comparison with CrNiMo steel with higher SFE. The micromechanism of the fracture in hydrogen-assisted surface layers of the steels is compositional, grain-size and hydrogen content dependent characteristic. The present results demonstrate that the steels with UFG structure possess higher resistance to hydrogen embrittlement compared to coarse-grained analogues.

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Hydrogen Embrittlement of Steels in High Pressure H2 Gas and Acidified H2S-saturated Aqueous Brine Solution

BHM Berg- und Hüttenmännische Monatshefte ◽

10.1007/s00501-021-01143-w ◽

2021 ◽

Author(s):

Anton Trautmann ◽

Gregor Mori ◽

Bernd Loder

Keyword(s):

Hydrogen Embrittlement ◽

Stainless Steels ◽

Austenitic Stainless Steels ◽

High Strength ◽

Hydrogen Uptake ◽

Constant Load ◽

Carbon Steels ◽

Hydrogen Gas ◽

Gas Reservoir ◽

Load Tests

AbstractMicrobiological methanation is planned in an underground natural gas reservoir. For this purpose, hydrogen is stored, which can lead to hydrogen embrittlement of steels. To simulate these field conditions, autoclave tests were performed to clarify the amount of absorbed hydrogen and to test whether this content leads to failure of the steels. Constant load tests and immersion tests with subsequent hydrogen analyses were performed. Tests under constant load have shown that no cracks occur due to hydrogen pressures up to 100 bar and temperatures at 25 °C and 80 °C. In these conditions, the carbon steels absorb a maximum of 0.54 ppm hydrogen, which is well below the embrittlement limit. Austenitic stainless steels absorb much more hydrogen, but these steels also have a higher resistance to hydrogen embrittlement. In H2S saturated solutions, the hydrogen uptake is ten times higher compared to hydrogen gas, which has caused fractures of several steels (high strength carbon steels, Super 13Cr, and Duplex stainless steel 2205).

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Screening Technique of Hydrogen Embrittlement Sensitivity in Austenitic Stainless Steels Using In-Situ Small Punch Test Method

Volume 6B: Materials and Fabrication ◽

10.1115/pvp2019-93738 ◽

2019 ◽

Author(s):

Hyung-Seop Shin ◽

Kyung-Oh Bae ◽

Hyuckmin Kim ◽

Un-Bong Baek ◽

Seung-Hoon Nahm

Keyword(s):

Hydrogen Embrittlement ◽

Stainless Steels ◽

Austenitic Stainless Steels ◽

Hydrogen Gas ◽

Test Method ◽

Austenitic Steels ◽

Hydrogen Energy ◽

Small Punch ◽

Screening Technique

Abstract In this study, a simple screening technique using an in-situ small-punch (SP) test and based on the hydrogen embrittlement (HE) sensitivity of austenitic stainless steels was developed for use in hydrogen energy facilities. To investigate the HE behaviors of metallic materials, the in-situ SP tests were carried out under high-pressure hydrogen gas environments. The reductions of thickness at the fractured parts of the specimen were measured. The relative reductions of thickness (RRT) were determined after conducting SP tests in both hydrogen and inert gas environments. Similar to the relative reduction of area (RRA) obtained using the slow strain-rate tensile test, RRT obtained using the in-situ SP test is a quantitative measure of the influence of the HE behaviors. The influence of punch velocity on HE sensitivity was examined. The HE behaviors of austenitic steels were evaluated qualitatively and quantitatively. The high-Mn steels were also evaluated because they are candidates for storage and transportation of hydrogen gas. A screening technique for determining the practical environmental conditions at the point of use could be established by confirming the effectiveness of the influencing factor, RRT, using this in-situ SP test method.

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