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

Author(s):  
Anton Trautmann ◽  
Gregor Mori ◽  
Bernd Loder

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).

2019 ◽  
Vol 165 (1) ◽  
pp. 40-45 ◽  
Author(s):  
Anton Trautmann ◽  
Gregor Mori ◽  
Wolfgang Siegl ◽  
Mathias Truschner ◽  
Josefine Pfeiffer ◽  
...  

AbstractMicrobiological methanation is investigated in an underground natural gas reservoir. Since H2 is involved in the process, hydrogen embrittlement of steel must inevitably be considered. Therefore, a routine for testing has been developed and a unique autoclave test bench was designed to simulate field conditions. The 2205 duplex stainless steel (UNS S31803) was investigated. Constant load tests (CLTs) and immersion tests with subsequent hydrogen analyses were performed. The specimens were exposed to different partial pressures of H2 under both dry and wet conditions (with brine). Additionally, the influence of CO2 under wet conditions was covered. Tests were performed at two different temperatures (25 °C and 80 °C) and lasted for 30 days. In general, the duplex stainless steel shows a good resistance to hydrogen embrittlement, but a significantly higher hydrogen uptake was obtained compared to other steel grades.


Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3604 ◽  
Author(s):  
Anton Trautmann ◽  
Gregor Mori ◽  
Markus Oberndorfer ◽  
Stephan Bauer ◽  
Christoph Holzer ◽  
...  

To avoid failures due to hydrogen embrittlement, it is important to know the amount of hydrogen absorbed by certain steel grades under service conditions. When a critical hydrogen content is reached, the material properties begin to deteriorate. The hydrogen uptake and embrittlement of three different carbon steels (API 5CT L80 Type 1, P110 and 42CrMo4) was investigated in autoclave tests with hydrogen gas (H2) at elevated pressure and in ambient pressure tests with hydrogen sulfide (H2S). H2 gas with a pressure of up to 100 bar resulted in an overall low but still detectable hydrogen absorption, which did not cause any substantial hydrogen embrittlement in specimens under a constant load of 90% of the specified minimum yield strength (SMYS). The amount of hydrogen absorbed under conditions with H2S was approximately one order of magnitude larger than under conditions with H2 gas. The high hydrogen content led to failures of the 42CrMo4 and P110 specimens.


2008 ◽  
Vol 575-578 ◽  
pp. 1002-1007 ◽  
Author(s):  
L. Pentti Karjalainen ◽  
Mahesh C. Somani ◽  
Atef S. Hamada

Processing of a large number of novel steel types, such as DP, TRIP, CP and TWIP, and high-strength low-carbon bainitic and martensitic DQ-T steels, have been developed based on physical simulation and modelling studies. Among stainless steels, guidelines for processing of ultra-fine grained austenitic stainless steels have been created. Physical simulation has been used by employing a Gleeble thermo-mechanical simulator to reveal the phenomena occurring in the hot rolling stage (the flow resistance, recrystallization kinetics and microstructure evolution), and in the cooling stage (CCT diagrams) for carbon steels and in short-term annealing of cold rolled metastable austenitic steels. Connecting these data with microstructures examined in optical and electron microscopes and resultant mechanical properties have improved the understanding on complex phenomena occurring in the processing of these steels and the role of numerous process variables in the optimization of enhanced mechanical properties.


2015 ◽  
Vol 33 (6) ◽  
pp. 515-527 ◽  
Author(s):  
Olga Todoshchenko ◽  
Yuriy Yagodzinskyy ◽  
Valentina Yagodzinska ◽  
Tapio Saukkonen ◽  
Hannu Hänninen

AbstractConstant load tests of high-strength carbon steels with different micro-alloying using strengths in the range of 1000–1400 MPa were performed at ambient temperature under continuous electrochemical hydrogen charging. Hydrogen markedly affects delayed fracture of all the studied steels. Fractography of the studied steels shows that fracture mechanism depends on the chemical composition of the studied steels and hydrogen-induced cracking exhibits intergranular or transgranular character occurring often in the form of hydrogen flakes. The size and chemical composition of non-metallic inclusions are analyzed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. Hydrogen-induced cracking initiates at TiN/TiC particles in steels with Ti alloying. Crack paths are studied with electron backscatter diffraction mapping to analyze crack initiation and growth. The thermal desorption spectroscopy method is used to analyze the distribution of hydrogen in the trapping sites. The mechanisms of hydrogen effects on fracture of high-strength steels are discussed.


Author(s):  
Hisatake Itoga ◽  
Takashi Matsuo ◽  
Akihiro Orita ◽  
Hisao Matsunaga ◽  
Saburo Matsuoka ◽  
...  

Slow strain rate tests (SSRTs) were performed with two types of high-strength austenitic stainless steels, Types AH and BX, as well as with two types of conventional austenitic stainless steels, Types 304 and 316L. The tests used the following combinations of specimen types and test atmospheres: (i) non-charged specimens tested in air, (ii) hydrogen-charged specimens tested in air (tests for internal hydrogen), and (iii) non-charged specimens tested in hydrogen gas at pressures of 78 ∼ 115 MPa (tests for external hydrogen). Type 304 exhibited a marked reduction of ductility in the tests for both internal hydrogen and external hydrogen, whereas Types AH, BX and 316L exhibited little or no degradation. In addition, fatigue crack growth (FCG) tests for the four types of steels were also carried out in air and hydrogen gas at pressures of 100 ∼ 115 MPa. In Type 304, FCG in hydrogen gas was more than 10 times as fast as that in air, whereas the acceleration rate remained within 1.5 ∼ 3 times in Types AH, BX and 316L. It was presumed that, in Types AH and BX, a small amount of additive elements, e.g. nitrogen and niobium, increased the strength as well as the stability of the austenitic phase, which thereby led to the excellent resistance against hydrogen.


Author(s):  
Hyung-Seop Shin ◽  
Kyung-Oh Bae ◽  
Hyuckmin Kim ◽  
Un-Bong Baek ◽  
Seung-Hoon Nahm

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.


Author(s):  
Osamu Takakuwa ◽  
Junichiro Yamabe ◽  
Hisao Matsunaga ◽  
Yoshiyuki Furuya ◽  
Saburo Matsuoka

Slow-strain rate tensile (SSRT) tests on various metals having γ-Fe phase; Type 304 and 316L stainless steels, HP160 high strength stainless steel, and A286 Fe-based super alloy were conducted in external hydrogen and with internal hydrogen. The external hydrogen indicates non-charged specimens tested in high-pressure hydrogen-gas environment, whereas the internal hydrogen indicates hydrogen-charged specimens, with uniform distribution of hydrogen, tested in inert gas. The hydrogen distribution was calculated based on the measured hydrogen diffusivity and solubility. The fracture morphologies were observed by scanning electron microscopy (SEM). For Types 304, 316L, and HP160, the relative reduction in area (RRA) of the steels was successfully reproduced by the nickel equivalent, Nieq, showing the higher Nieq, the lager RRA. Furthermore, at a low Nieq, the RRA of the steel with external hydrogen was nearly equal to that with internal hydrogen. In contrast, at a high Nieq, the RRA of the steel with internal hydrogen was slightly degraded by hydrogen, RRA ≈ 0.8, whereas that in external hydrogen was not degraded, RRA ≈ 1. For A286, despite a high Nieq, the RRA of the alloy with internal hydrogen was significantly degraded by hydrogen, RRA ≈ 0.5. The fracture morphologies were categorized into four types: quasi-cleavage fracture associated with hydrogen-assisted surface cracks; ordinary void formation with no hydrogen effect; small-void formation associated with void sheet enhanced by hydrogen; facet formation induced by hydrogen. These categorized morphologies could be interpreted in terms of hydrogen distribution (internal or external hydrogen), austenitic stability (a low or high Nieq), and microstructure (solution or precipitation-hardened treatment).


2018 ◽  
Vol 165 ◽  
pp. 22002
Author(s):  
Sven Brück ◽  
Volker Schippl ◽  
Hans-Jürgen Christ ◽  
Claus-Peter Fritzen

In the present study, the influence of hydrogen on the fatigue behaviour of the high strength martensitic stainless steel X3CrNiMo13-4 and the metastable austenitic stainless steels X2Crni19-11 with various nickel contents was examined in the low and high cycle fatigue regime. The focus of the investigations was the changes in the mechanisms of short crack propagation. The aim of the ongoing investigation is to determine and quantitatively describe the predominant processes of hydrogen embrittlement and their influence on the short fatigue crack morphology and crack growth rate. In addition, simulations were carried out on the short fatigue crack growth, in order to develop a detailed insight into the hydrogen embrittlement mechanisms relevant for cyclic loading conditions.


Author(s):  
Masaaki Imade ◽  
Lin Zhang ◽  
Bai An ◽  
Takashi Iijima ◽  
Seiji Fukuyama ◽  
...  

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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