Статті в журналах: "Steel Hydrogen embrittlement Testing"

1

Martins, Franc A., J. A. Ponciano, and Ivani de S. Bott. "Saw Welded Joints of Two API Steels Subject to SCC Laboratory Testing." Materials Science Forum 539-543 (March 2007): 4440–45. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.4440.

Повний текст джерела

Анотація:

Many steels tubes used in the Oil Industry are constantly exposed to hydrogen sulphide (H2S) which can lead to the diffusion of hydrogen into the steel, potentially provoking hydrogen embrittlement and/or stress corrosion cracking. Additionally the critical region in pipelines is usually considered to be the welded joints. In this work SAW welded joints of two API steels, grades X80 and X70, were evaluated using laboratory tests according to the NACE TM0177/96 METHOD A Standard and the slow strain rate test (SSRT) using a sodium thiosulphate solution. The results indicate that both steel grades can be susceptible to HE and SCC, since loss of ductility when submitted to SSRT and failure under NACE TM0177/96 METHOD A were observed.

Стилі APA, Harvard, Vancouver, ISO та ін.

2

Liu, Bo, Xiaolin Liao, Yuanshou Tang, Yu Si, Yi Feng, Pengjun Cao, Qingwei Dai, and Kejian Li. "Effects of the Addition of Nb and V on the Microstructural Evolution and Hydrogen Embrittlement Resistance of High Strength Martensitic Steels." Scanning 2022 (February 24, 2022): 1–9. http://dx.doi.org/10.1155/2022/4040800.

Повний текст джерела

Анотація:

Hydrogen embrittlement can easily occur in high strength martensitic steel, manifesting itself as a sudden failure or fracture without warning and greatly threatening the safety of automotive applications. Optimizing the composition of the alloy can be performed by matching heat treatment processing methods and controlling the precipitation amounts to form hydrogen traps. In doing so, the hydrogen embrittlement susceptibility of steel can be effectively delayed, reducing the risk of hydrogen-induced delayed cracking. In this study, four kinds of 1500 MPa strength grade martensitic steel were selected for testing and supplemented with different loadings of Nb and V, respectively. Their grains, phases, and precipitations were compared by optical microscopy (OM), electron backscattered diffraction (ESBD), and transmission electron microscopy (TEM) analyses. After the addition of Nb and V, the microstructure was refined, the residual austenite content increased, and the hydrogen embrittlement resistance was significantly improved.

Стилі APA, Harvard, Vancouver, ISO та ін.

3

Zhou, Haiting, Dongdong Ye, Jianjun Chen, Qiang Wang, and Xinwei Fan. "Discussion on the characterisation of hydrogen embrittlement based on eddy current signals." Insight - Non-Destructive Testing and Condition Monitoring 62, no. 1 (January 1, 2020): 11–14. http://dx.doi.org/10.1784/insi.2020.62.1.11.

Повний текст джерела

Анотація:

A non-destructive testing (NDT) method for evaluating mechanical performance has been studied based on the analysis of eddy current signals. Low-alloy steel samples were tested under conditions of tension with the aim of quantifying hydrogen embrittlement (HE). The mechanical responses of samples were investigated after electrochemical hydrogen charging. Eddy current signals were gathered to evaluate the hydrogen embrittlement state using a differential probe. Numerical analysis of hydrogen concentration distribution in material was performed to investigate the response mechanism of the signal. The effect that hydrogen has on the mechanical performance of low-alloy steel has been discussed. The experimental results show that the eddy current signal has a good correlation with the hydrogen-induced plasticity loss index.

Стилі APA, Harvard, Vancouver, ISO та ін.

4

Rodoni, Esteban, Andreas Viereckl, Zakaria Quadir, Aaron Dodd, Kim Verbeken, Tom Depover, and Mariano Iannuzzi. "Hydrogen Stress Cracking Resistance and Hydrogen Transport Properties of ASTM A508 Grade 4N." Corrosion 78, no. 1 (December 2, 2021): 96–111. http://dx.doi.org/10.5006/3949.

Повний текст джерела

Анотація:

Low alloy steels combine relatively low cost with exceptional mechanical properties, making them commonplace in oil and gas equipment. However, their strength and hardness are restricted for sour environments to prevent different forms of hydrogen embrittlement. Materials used in sour services are regulated by the ISO 15156-2 standard, which imposes a maximum hardness of 250 HV (22 HRC) and allows up to 1.0 wt% Ni additions due to hydrogen embrittlement concerns. Low alloy steels that exceed the ISO 15156-2 limit have to be qualified for service, lowering their commercial appeal. As a result, high-performing, usually high-nickel, low alloy steels used successfully in other industries are rarely considered for sour service. In this work, the hydrogen stress cracking resistance of the high-nickel (3.41 wt%), quenched and tempered, nuclear-grade ASTM A508 Gr.4N low alloy steel was investigated using slow strain rate testing as a function of applied cathodic potential. Results showed that the yield strength and ultimate tensile strength were unaffected by hydrogen, even at a high negative potential of −2.00 VAg/AgCl. Hydrogen embrittlement effects were observed once the material started necking, manifested by a loss in ductility with increasing applied cathodic potentials. Indeed, A508 Gr.4N was less affected by hydrogen at high cathodic potentials than a low-strength (yield strength = 340 MPa) ferritic-pearlitic low alloy steel of similar nickel content. Additionally, hydrogen diffusivity was measured using the hydrogen permeation test. The calculated hydrogen diffusion coefficient of the ASTM A508 Gr.4N was two orders of magnitude smaller when compared to that of ferritic-pearlitic steels. Hydrogen embrittlement and diffusion results were linked to the microstructure features. The microstructure consisted of a bainitic/martensitic matrix with the presence of Cr23C6 carbides as well as Mo- and V-rich precipitates, which might have played a role in retarding hydrogen diffusion, kept responsible for the improved HE resistance.

Стилі APA, Harvard, Vancouver, ISO та ін.

5

Trautmann, Anton, Gregor Mori, Wolfgang Siegl, Mathias Truschner, Josefine Pfeiffer, Marianne Kapp, Andreas Keplinger, Markus Oberndorfer, and Stephan Bauer. "Hydrogen Uptake of Duplex 2205 at H2 Partial Pressures up to 100 bar." BHM Berg- und Hüttenmännische Monatshefte 165, no. 1 (December 20, 2019): 40–45. http://dx.doi.org/10.1007/s00501-019-00934-6.

Повний текст джерела

Анотація:

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.

Стилі APA, Harvard, Vancouver, ISO та ін.

6

Ebling, Fabien, Silke Klitschke, Ken Wackermann, and Johannes Preußner. "The Effect of Hydrogen on Failure of Complex Phase Steel under Different Multiaxial Stress States." Metals 12, no. 10 (October 12, 2022): 1705. http://dx.doi.org/10.3390/met12101705.

Повний текст джерела

Анотація:

The demand for advanced high-strength steel (AHSS) in the automotive industry has increased over the last few years. Nevertheless, it is known that AHSSs are susceptible to hydrogen embrittlement. Therefore, the influence of hydrogen on the localization and damage behavior of a CP1000 steel sheet was investigated in this work. The sheet metal was electrochemically charged to a hydrogen content of about 3 ppm (by weight). Tensile tests were performed at different nominal strain rates between 0.00004 s−1 and 0.01 s−1 to investigate the effects of strain rates on their susceptibility to hydrogen embrittlement. Nakajima tests were utilized to investigate the hydrogen effects on the steel’s formability under different stress states. Three different Nakajima specimen geometries were employed to represent a uniaxial stress state, a nearly plane strain stress state, and an equibiaxial stress state. Further, forming limits were evaluated with the standardized section line method. Hydrogen embrittlement, during tensile testing, occurred independent of the strain rate, unlike the Nakajima test results, which showed hydrogen effects that were strongly dependent on the stress state.

Стилі APA, Harvard, Vancouver, ISO та ін.

7

Li, Jinbo, Xiuhua Gao, Hongwei Chen, Hongyan Wu, Linxiu Du, and Chen Chen. "Hydrogen Embrittlement Susceptibility of Corrosion-Resistant Spring Rod Used in High-Speed Railway." Metals 13, no. 1 (January 11, 2023): 147. http://dx.doi.org/10.3390/met13010147.

Повний текст джерела

Анотація:

The corrosion of spring steel is very important for vehicle safety. In this work, we conducted an experiment on multi-element micro-alloy composition design; the corrosion resistance of a 60Si2Mn spring was improved by adding Cr, Ni, Cu and other corrosion-resistant elements, and the corrosion resistance index (I) was increased from 3.21 to 8.62. Hydrogen embrittlement resistance was studied using a hydrogen permeation experiment and a slow strain rate tensile experiment. For this study, the following steps were performed: Firstly, the material composition was designed, and the experimental materials that met the experimental design were prepared according to the corresponding deformation and heat treatment process; secondly, the experimental materials were charged with hydrogen; and finally, conventional tensile testing, slow tensile testing and fracture morphology testing were carried out. A hydrogen permeation experiment was carried out for the materials. The result showed that, with the increase of hydrogen charging time, the hydrogen content of two steel samples increased, and the plasticity indexes such as elongation and reduction of the area appeared in three different stages which rapidly decreased, slowly declined, and then tended to balance. The uniform NbC nano precipitated phase can double the number of irreversible hydrogen traps (Nir) per unit volume, and decreased the effective hydrogen diffusion coefficient (Deff) from 1.135 × 10−10 to 6.036 × 10−11. It limited the free diffusion of hydrogen and made the immersed hydrogen harmless, thus improving the hydrogen embrittlement resistance of corrosion-resistant spring steel 60Si2Mn.

Стилі APA, Harvard, Vancouver, ISO та ін.

8

Titov, Anatolii I., Aleksandr V. Lun-Fu, Aleksandr V. Gayvaronskiy, Mikhail A. Bubenchikov, Aleksei M. Bubenchikov, Andrey M. Lider, Maxim S. Syrtanov, and Viktor N. Kudiiarov. "Hydrogen Accumulation and Distribution in Pipeline Steel in Intensified Corrosion Conditions." Materials 12, no. 9 (April 30, 2019): 1409. http://dx.doi.org/10.3390/ma12091409.

Повний текст джерела

Анотація:

Hydrogen accumulation and distribution in pipeline steel under conditions of enhanced corrosion has been studied. The XRD analysis, optical spectrometry and uniaxial tension tests reveal that the corrosion environment affects the parameters of the inner and outer surface of the steel pipeline as well as the steel pipeline bulk. The steel surface becomes saturated with hydrogen released as a reaction product during insignificant methane dissociation. Measurements of the adsorbed hydrogen concentration throughout the steel pipe bulk were carried out. The pendulum impact testing of Charpy specimens was performed at room temperature in compliance with national standards. The mechanical properties of the steel specimens were found to be considerably lower, and analogous to the properties values caused by hydrogen embrittlement.

Стилі APA, Harvard, Vancouver, ISO та ін.

9

Law, M., and D. Nolan. "Test Methods to Assess Transverse Weld Metal Hydrogen Cracking." Advanced Materials Research 41-42 (April 2008): 427–34. http://dx.doi.org/10.4028/www.scientific.net/amr.41-42.427.

Повний текст джерела

Анотація:

Hydrogen cracking in steel weldments can drastically reduce the toughness and ductility of welds in steel structures. Unfortunately, the development of the hydrogen economy will also see materials being increasingly exposed to hydrogen, in processes such as during hydrogen production and transportation. Thus, test methods are required which allow for a reproducible assessment of hydrogen embrittlement in weld material. In this article, rectangular test specimens made from weld bead on plate samples were subject to 4-point bend testing to investigate the relationship between applied stress, hydrogen content and embrittlement. This test concentrates the stresses in the weld bead, thus reducing the effects of premature HAZ cracking and enabling failure to develop in the weld metal, and showed good reproducibility. This test may form the basis for an industry test. Another test method is described using an un-machined weld bead on plate. A method of calculating the stresses and strains in this specimen in 4-point bending was developed.

Стилі APA, Harvard, Vancouver, ISO та ін.

10

Artola, Garikoitz, and Javier Aldazabal. "Hydrogen Assisted Fracture of 30MnB5 High Strength Steel: A Case Study." Metals 10, no. 12 (November 30, 2020): 1613. http://dx.doi.org/10.3390/met10121613.

Повний текст джерела

Анотація:

When steel components fail in service due to the intervention of hydrogen assisted cracking, discussion of the root cause arises. The failure is frequently blamed on component design, working conditions, the manufacturing process, or the raw material. This work studies the influence of quench and tempering and hot-dip galvanizing on the hydrogen embrittlement behavior of a high strength steel. Slow strain rate tensile testing has been employed to assess this influence. Two sets of specimens have been tested, both in air and immersed in synthetic seawater, at three process steps: in the delivery condition of the raw material, after heat treatment and after heat treatment plus hot-dip galvanizing. One of the specimen sets has been tested without further manipulation and the other set has been tested after applying a hydrogen effusion treatment. The outcome, for this case study, is that fracture risk issues only arise due to hydrogen re-embrittlement in wet service.

Стилі APA, Harvard, Vancouver, ISO та ін.

11

Shin, Hyung-Seop, Juho Yeo, and Un-Bong Baek. "Influence of Specimen Surface Roughness on Hydrogen Embrittlement Induced in Austenitic Steels during In-Situ Small Punch Testing in High-Pressure Hydrogen Environments." Metals 11, no. 10 (October 4, 2021): 1579. http://dx.doi.org/10.3390/met11101579.

Повний текст джерела

Анотація:

An in-situ small punch (SP) test method has recently been developed as a simple screening technique for evaluating the properties of metallic materials used in high-pressure hydrogen environments. With this method, the test conditions including temperature and gas pressure can easily be adjusted to those used in practice. In this study, specimens of STS316L steel and 18 wt% Mn steel were prepared at two different surface roughness, fabricated using wire-cutting and mechanical polishing. Their effects on hydrogen embrittlement (HE) were evaluated using in-situ SP testing at both room temperature and a lower temperature where HE was shown to occur under 10 MPa hydrogen. Both steels were evaluated using two variables obtained from in-situ SP testing, the SP energy, and the relative reduction of thickness (RRT), to quantitatively determine the effect of specimen surface roughness on HE susceptibility. Their fracture characteristics due to HE under 10 MPa hydrogen showed little difference with surface finish. Surface roughness had a negligible influence on these quantitative factors describing HE, indicating that it is not a dominant factor to be considered in in-situ SP testing when it is used to screen for HE compatibility in steels used in high-pressure hydrogen environments.

Стилі APA, Harvard, Vancouver, ISO та ін.

12

Ramkumar, K. Devendranath, G. Gopi, Ravi Prasad Valluri, K. Sampath Kumar, Trilochana Jena, and M. Nageswara Rao. "Environment-Induced Degradation in Maraging Steel Grade 18Ni1700." Materials Science Forum 941 (December 2018): 407–12. http://dx.doi.org/10.4028/www.scientific.net/msf.941.407.

Повний текст джерела

Анотація:

Samples extracted from flow formed tubes made of 18% nickel maraging steel grade C18Ni1750 were subjected to tensile testing at room temperature in laboratory environment at two different strain rates. Testing was carried out in as flow formed as well as flow formed and aged conditions. Aging was carried out adopting four different cycles. Distinct loss of ductility was observed at the lower strain rate in all tested conditions. The embrittlement occurring during low strain rate testing is explained in terms of hydrogen induced damage, hydrogen coming from the moisture in the environment. It is also concluded that the heavy cold work imparted to the material during flow-forming is importantly responsible for the ductility loss observed at low strain rate.

Стилі APA, Harvard, Vancouver, ISO та ін.

13

Nykyforchyn, Hryhoriy, Olha Zvirko, Myroslava Hredil, Halyna Krechkovska, Oleksandr Tsyrulnyk, Oleksandra Student, and Leonid Unigovskyi. "Methodology of hydrogen embrittlement study of long-term operated natural gas distribution pipeline steels caused by hydrogen transport." Frattura ed Integrità Strutturale 16, no. 59 (December 22, 2021): 396–404. http://dx.doi.org/10.3221/igf-esis.59.26.

Повний текст джерела

Анотація:

A methodology of experimental research on hydrogen embrittlement of pipe carbon steels due to the transportation of hydrogen or its mixture with natural gas by a long-term operated gas distribution network is presented. The importance of comparative assessments of the steel in the as-received and operated states basing on the properties that characterize plasticity, resistance to brittle fracture and hydrogen assisted cracking is accentuated. Two main methodological peculiarities are pointed out, (i) testing specimens should be cut out in the transverse direction relative to the pipe axis; (ii) strength and plasticity characteristics should be determined using flat tensile specimens with the smallest possible thickness of the working part. The determination of hydrogen concentration in metal, metallographic and fractographic analyses have been supplemented the study. The effectiveness of the proposed methodology has been illustrated by the example of the steel research after its 52-year operation.

Стилі APA, Harvard, Vancouver, ISO та ін.

14

De Seranno, Tim, Ellen Lambrechts, Evelyn De Meyer, Wolfgang Hater, Nathalie De Geyter, Arne R. D. Verliefde, Tom Depover, and Kim Verbeken. "Effect of Film-Forming Amines on the Acidic Stress-Corrosion Cracking Resistance of Steam Turbine Steel." Metals 10, no. 12 (December 4, 2020): 1628. http://dx.doi.org/10.3390/met10121628.

Повний текст джерела

Анотація:

This work evaluates the effect of film-forming amines (FFA) on the acidic stress-corrosion cracking (SCC) resistance of NiCrMoV turbine steel. Contact angle measurements show an increased hydrophobicity of the surface when coating the steel with oleyl propylene diamine (OLDA). According to potentiodynamic measurements and post-mortem scanning electron microscopy (SEM) analysis, anodic dissolution and hydrogen embrittlement still occur when the steel is FFA coated. In situ constant extension rate testing (CERT) in acidic aqueous environment at elevated temperature of FFA-coated steel shows a ductility gain compared to non-coated steel, explained by a decrease in both corrosion rate and hydrogen uptake.

Стилі APA, Harvard, Vancouver, ISO та ін.

15

Fussik, Robert, Gero Egels, Werner Theisen, and Sebastian Weber. "Investigation of the Local Austenite Stability Related to Hydrogen Environment Embrittlement of Austenitic Stainless Steels." Materials Science Forum 941 (December 2018): 263–68. http://dx.doi.org/10.4028/www.scientific.net/msf.941.263.

Повний текст джерела

Анотація:

Hydrogen is increasingly considered as fuel for future mobility or for stationary applications. However, the safe distribution and storage of pure hydrogen is only possible with suitable materials. Interstitially dissolved hydrogen atoms in the lattice of numerous metals are responsible for hydrogen embrittlement (HE). If hydrogen is introduced by an external source, it is called hydrogen environment embrittlement (HEE). Commonly, steels like AISI 316L with a high resistance to HEE include a large number of alloying elements and in high amount. High alloying levels result in a decrease of cost-efficiency. Therefore, the systematic investigation of lean-alloyed austenitic stainless steels is necessary in order to understand the mechanism of HEE. For that purpose, the steel grades AISI 304L and AISI 316L are selected in this work. Tensile tests in air and 400 bar hydrogen gas atmospheres are performed. After tensile testing in H, AISI 304L revealed secondary cracks at the specimen surface, which are related to the local austenite stability, which in turn is affected by the level of micro-segregation. The microstructural investigations of the crack environment directly contribute to the understanding of the micro-mechanisms of HEE. Property-maps generated from experimentally measured distributions of alloying elements allow to correlate the impact of micro-segregations on the local austenite stability. It is shown, that local segregation-bands affect the initiation and propagation of secondary cracks. In this context, the local austenite stability which is significantly affected by the Ni distribution will be discussed in detail by comparison of the metastable austenitic steel grades AISI 304L and AISI 316L.

Стилі APA, Harvard, Vancouver, ISO та ін.

16

Wang, Yanfei, Xuanpei Wu та Weijie Wu. "Effect of α′ Martensite Content Induced by Tensile Plastic Prestrain on Hydrogen Transport and Hydrogen Embrittlement of 304L Austenitic Stainless Steel". Metals 8, № 9 (23 серпня 2018): 660. http://dx.doi.org/10.3390/met8090660.

Повний текст джерела

Анотація:

Effects of microstructural changes induced by prestraining on hydrogen transport and hydrogen embrittlement (HE) of austenitic stainless steels were studied by hydrogen precharging and tensile testing. Prestrains higher than 20% at 20 °C significantly enhance the HE of 304L steel, as they induce severe α′ martensite transformation, accelerating hydrogen transport and hydrogen entry during subsequent hydrogen exposure. In contrast, 304L steel prestrained at 50 and 80 °C and 316L steel prestrained at 20 °C exhibit less HE, due to less α′ after prestraining. The increase of dislocations after prestraining has a negligible influence on apparent hydrogen diffusivity compared with pre-existing α′. The deformation twins in heavily prestrained 304L steel can modify HE mechanism by assisting intergranular (IG) fracture. Regardless of temperature and prestrain level, HE and apparent diffusivity ( D app ) increase monotonously with α′ volume fraction ( f α ′ ). D app can be described as log D app = log ( D α ′ s α ′ / s γ ) + log [ f α ′ / ( 1 − f α ′ ) ] for 10 % < f α ′ < 90 % , with D α ′ is diffusivity in α′, s α ′ and s γ are solubility in α′ and austenite, respectively. The two equations can also be applied to these more typical duplex materials containing both BCC and FCC phases.

Стилі APA, Harvard, Vancouver, ISO та ін.

17

Funahashi, Miki, and Walter T. Young. "Cathodic Protection of Prestressed Bridge Members—Full-Scale Testing." Transportation Research Record: Journal of the Transportation Research Board 1561, no. 1 (January 1996): 13–25. http://dx.doi.org/10.1177/0361198196156100103.

Повний текст джерела

Анотація:

The results of a study on the use of cathodic protection on prestressed and post-tensioned concrete bridge members are summarized. Previous laboratory tests to evaluate hydrogen embrittlement of high strength steel embedded in concrete have proven that cathodic protection will generate hydrogen on high-strength steel in concrete if the potential is more negative than the thermodynamic hydrogen evolution potential. The hydrogen generated will enter the steel and cause a loss in ductility that will adversely affect the steel's performance if a notch is present. Full-scale beams were constructed to further study those phenomena. Four pretensioned beams were constructed. In addition, two post-tensioned slabs were constructed to evaluate cathodic protection of anchorages and tendons encased in metal or plastic conduits. Cathodic protection currents were supplied by IR drop-free potential controlled rectifiers. Good potential control at control points was achieved by using externally mounted silver-silver chloride reference electrodes and a conductive gel bridge. However, inconsistent potential control occurred at locations other than at the control points. Later in the study, constant current power supplies were used on two of the beams. Hydrogen entering the steel as the result of corrosion appears to have masked the presence of hydrogen that might have been produced by cathodic protection. The analysis also revealed that there was corrosion of some pretensioned wires at crossings with interior steel reinforcing bars due to interference (stray current) caused by cathodic protection application. Analysis of the post-tensioned slabs indicated little effect of cathodic protection on tendons inside plastic or metal ducts from the application of cathodic protection. Beneficial effects were noted on anchor points where mortar was in contact with the metal.

Стилі APA, Harvard, Vancouver, ISO та ін.

18

Kyriakopoulou, Helen, Panagiotis Karmiris-Obratański, Athanasios Tazedakis, Nikoalos Daniolos, Efthymios Dourdounis, Dimitrios Manolakos, and Dimitrios Pantelis. "Investigation of Hydrogen Embrittlement Susceptibility and Fracture Toughness Drop after in situ Hydrogen Cathodic Charging for an X65 Pipeline Steel." Micromachines 11, no. 4 (April 20, 2020): 430. http://dx.doi.org/10.3390/mi11040430.

Повний текст джерела

Анотація:

The present research focuses on the investigation of an in situ hydrogen charging effect during Crack Tip Opening Displacement testing (CTOD) on the fracture toughness properties of X65 pipeline steel. This grade of steel belongs to the broader category of High Strength Low Alloy Steels (HSLA), and its microstructure consists of equiaxed ferritic and bainitic grains with a low volume fraction of degenerated pearlite islands. The studied X65 steel specimens were extracted from pipes with 19.15 mm wall thickness. The fracture toughness parameters were determined after imposing the fatigue pre-cracked specimens on air, on a specific electrolytic cell under a slow strain rate bending loading (according to ASTM G147-98, BS7448, and ISO12135 standards). Concerning the results of this study, in the first phase the hydrogen cations’ penetration depth, the diffusion coefficient of molecular and atomic hydrogen, and the surficial density of blisters were determined. Next, the characteristic parameters related to fracture toughness (such as J, KQ, CTODel, CTODpl) were calculated by the aid of the Force-Crack Mouth Open Displacement curves and the relevant analytical equations.

Стилі APA, Harvard, Vancouver, ISO та ін.

19

Artola, Garikoitz, Alberto Arredondo, Ana Fernández-Calvo, and Javier Aldazabal. "Hydrogen Embrittlement Susceptibility of R4 and R5 High-Strength Mooring Steels in Cold and Warm Seawater." Metals 8, no. 9 (September 6, 2018): 700. http://dx.doi.org/10.3390/met8090700.

Повний текст джерела

Анотація:

Hydrogen embrittlement susceptibility ratios calculated from slow strain rate tensile tests have been employed to study the response of three high-strength mooring steels in cold and warm synthetic seawater. The selected nominal testing temperatures have been 3 °C and 23 °C in order to resemble sea sites of offshore platform installation interest, such as the North Sea and the Gulf of Mexico, respectively. Three scenarios have been studied for each temperature: free corrosion, cathodic protection and overprotection. An improvement on the hydrogen embrittlement tendency of the steels has been observed when working in cold conditions. This provides a new insight on the relevance of the seawater temperature as a characteristic to be taken into account for mooring line design in terms of hydrogen embrittlement assessment.

Стилі APA, Harvard, Vancouver, ISO та ін.

20

Thiessen, R. G. "Hydrogen-related challenges for the steelmaker: the search for proper testing." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375, no. 2098 (June 12, 2017): 20160408. http://dx.doi.org/10.1098/rsta.2016.0408.

Повний текст джерела

Анотація:

The modern steelmaker of advanced high-strength steels has always been challenged with the conflicting targets of increased strength while maintaining or improving ductility. These new steels help the transportation sector, including the automotive sector, to achieve the goals of increased passenger safety and reduced emissions. With increasing tensile strengths, certain steels exhibit an increased sensitivity towards hydrogen embrittlement (HE). The ability to characterize the material's sensitivity in an as-delivered condition has been developed and accepted (SEP1970), but the complexity of the stress states that can induce an embrittlement together with the wide range of applications for high-strength steels make the development of a standardized test for HE under in-service conditions extremely challenging. Some proposals for evaluating the material's sensitivity give an advantage to materials with a low starting ductility. Despite this, newly developed materials can have a higher original elongation with only a moderate reduction in elongation due to hydrogen. This work presents a characterization of new materials and their sensitivity towards HE. This article is part of the themed issue ‘The challenges of hydrogen and metals’.

Стилі APA, Harvard, Vancouver, ISO та ін.

21

Kobayashi, Kenji, Tomohiko Omura, and Masakatsu Ueda. "Effect of Testing Temperature on Sulfide Stress Cracking of Low Alloy Steel." Corrosion 74, no. 6 (January 9, 2018): 603–12. http://dx.doi.org/10.5006/2605.

Повний текст джерела

Анотація:

In this study, effects of environmental temperature on susceptibility to sulfide stress cracking (SSC)—a type of hydrogen embrittlement (HE) occurring in sour environments—of low alloy steels were investigated from the perspective of hydrogen entry, absorption, and accumulation. SSC susceptibility was evaluated using a double cantilever beam (DCB) test and a four-point bend (4PB) test in sour environments at several testing temperatures. 4PB test specimens included notched and un-notched specimens to investigate influences of stress concentration and local stress. In the case of evaluation methods using specimens with high-stress concentration area, a decrease in testing temperature from room temperature to 4°C significantly increased SSC susceptibility. Hydrogen entry and absorption behaviors were also evaluated at several testing temperatures using a hydrogen permeation test. The hydrogen concentration at the plastic deformed area increased remarkably with decreasing testing temperature. It is considered that the influence of testing temperature is due to hydrogen concentration at the stress concentration area with plastic deformation. In a low temperature condition, the degree of hydrogen accumulation at the crack tip areas of a DCB specimen or crack initiation site of a 4PB specimen could be higher than that in a higher temperature condition. When steels are applied to low temperature conditions with H2S, a prior material evaluation reproducing both environmental temperature and actual stress condition is needed.

Стилі APA, Harvard, Vancouver, ISO та ін.

22

TAKEDA, Sho, Eri TOKUDA, Tetsuya UCHIMOTO, Toshiyuki TAKAGI, Hiroki YAMAMOTO, Takashi IIJIMA, and Hirotoshi ENOKI. "Evaluation of Phase Transformation by Eddy Current Testing in Hydrogen Embrittlement Testing of Austenitic Stainless Steel." Proceedings of the Materials and Mechanics Conference 2019 (2019): OS0610. http://dx.doi.org/10.1299/jsmemm.2019.os0610.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

23

Xu, Xiu Qing, Jing Niu, Cheng Zheng Li, Hang Juan Huang, and Cheng Xian Yin. "Comparative Study on Hydrogen Embrittlement Susceptibility in Heat-Affected Zone of TP321 Stainless Steel." Materials Science Forum 993 (May 2020): 568–74. http://dx.doi.org/10.4028/www.scientific.net/msf.993.568.

Повний текст джерела

Анотація:

TP321 stainless steel is widely used in hydrogenation refining pipes owing to its excellent performance of creep stress resistance and high-temperature resistance. In this study, thermal simulation tests were carried out on the welding heat-affected zone (HAZ) of TP321 stainless steel at temperatures of 1300 °C, 1100 °C, and 850°C using a Gleeble 3800 testing machine. Slow strain tensile tests were conducted under the condition of electrolytic hydrogen charging (EHC) and the metallographic microstructure of cracks as well as the morphology of fractures were analyzed in detail. The result shows that hydrogen can change the fracture mode of tensile specimen and the cracks initiated from and near the specimen surface after EHC. Hydrogen significantly decreases the plastic deformation capability of HAZ in TP321 stainless steel. The reduction of area after the fracture decreases by 58%, 41%, and 45% for HAZ at 1300 °C, 1100 °C, and 850 °C, respectively. The existence of δ ferrite was considered to be the main reason for the aggravation of hydrogen-induced plasticity loss.

Стилі APA, Harvard, Vancouver, ISO та ін.

24

Jonšta, P., P. Váňová, S. Brožová, P. Pustějovská, J. Sojka, Z. Jonšta, and M. Ingaldi. "Hydrogen Embrittlement of Welded Joint Made of Supermartensitic Stainless Steel in Environment Containing Sulfane." Archives of Metallurgy and Materials 61, no. 2 (June 1, 2016): 709–12. http://dx.doi.org/10.1515/amm-2016-0121.

Повний текст джерела

Анотація:

Abstract The work is focused on evaluation of resistance of the welded joint made of supermartensitic 13Cr6Ni2.5Mo stainless steel to sulfide stress cracking. Testing method A and solution B in accordance with NACE TM 0177 were used. All the testing samples were ruptured in a very short time interval but welded joint samples were fractured primarily in the weld metal or in heat affected zone and not in the basic material. Material analysis of samples were made with use of a ZEISS NEOPHOT 32 light microscope and a JEOL 6490LV scanning electron microscope.

Стилі APA, Harvard, Vancouver, ISO та ін.

25

Massone, Agustina, Armin Manhard, Andreas Drexler, Christian Posch, Werner Ecker, Verena Maier-Kiener, and Daniel Kiener. "Addressing H-Material Interaction in Fast Diffusion Materials—A Feasibility Study on a Complex Phase Steel." Materials 13, no. 20 (October 20, 2020): 4677. http://dx.doi.org/10.3390/ma13204677.

Повний текст джерела

Анотація:

Hydrogen embrittlement (HE) is one of the main limitations in the use of advanced high-strength steels in the automotive industry. To have a better understanding of the interaction between hydrogen (H) and a complex phase steel, an in-situ method with plasma charging was applied in order to provide continuous H supply during mechanical testing in order to avoid H outgassing. For such fast-H diffusion materials, only direct observation during in-situ charging allows for addressing H effects on materials. Different plasma charging conditions were analysed, yet there was not a pronounced effect on the mechanical properties. The H concentration was calculated while using a simple analytical model as well as a simulation approach, resulting in consistent low H values, below the critical concentration to produce embrittlement. However, the dimple size decreased in the presence of H and, with increasing charging time, the crack propagation rate increased. The rate dependence of flow properties of the material was also investigated, proving that the material has no strain rate sensitivity, which confirmed that the crack propagation rate increased due to H effects. Even though the H concentration was low in the experiments that are presented here, different technological alternatives can be implemented in order to increase the maximum solute concentration.

Стилі APA, Harvard, Vancouver, ISO та ін.

26

Hojo, Tomohiko, Hiroyuki Waki, and Fumihito Nishimura. "Evaluation for Hydrogen Embrittlement Properties of Tempered Martensitic Steel Sheets Using Several Testing Technique." Tetsu-to-Hagane 100, no. 10 (2014): 1306–14. http://dx.doi.org/10.2355/tetsutohagane.100.1306.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

27

Xue, Jinxin, Hao Wu, Chilou Zhou, Yuanming Zhang, Mohan He, Xinrui Yan, Huiyu Xie, Rui Yan, and Yansheng Yin. "Effect of Heat Input on Hydrogen Embrittlement of TIG Welded 304 Austenitic Stainless Steel." Metals 12, no. 11 (November 13, 2022): 1943. http://dx.doi.org/10.3390/met12111943.

Повний текст джерела

Анотація:

Welds made with 304 austenitic stainless steel play an important role in high-pressure hydrogen storage systems. However, there are few investigations of the effect of heat input on the hydrogen embrittlement (HE) of tungsten inert gas (TIG) welded 304 austenitic stainless steel. In this study, the effect of heat input on the HE of TIG welded 304 austenitic stainless steel is investigated. It was found that with the increase in TIG welding heat input, the ferrite content in the weld shows a tendency to first increase and then decrease. From the perspective of morphology, it first changes from lathy ferrite and strip ferrite to dendritic ferrite, and then becomes reticular ferrite and lathy ferrite. Slow strain rate tensile (SSRT) testing shows that with the increase in heat input from TIG welding, the susceptibility of the weld to HE first increases and then decreases. Our study shows that TIG welds of 304 austenitic stainless steel exhibit the best HE resistance when the welding heat input is 0.778 kJ/mm, the relative elongation (RE) is 0.884, and the relative reduction of area (RRA) is 0.721. This work can provide a reference for the optimization of the 304 stainless steel TIG welding process.

Стилі APA, Harvard, Vancouver, ISO та ін.

28

Mironov, Vladimir I., Igor G. Emel'yanov, and Olga A. Lukashuk. "Criteria of Material Failure in Relation to Hydrogen Saturation." Solid State Phenomena 316 (April 2021): 484–89. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.484.

Повний текст джерела

Анотація:

A steadily rising interest which specialists in various fields show towards the problem of hydrogen affecting metallic materials and causing their failure is connected to all-increasing requirements set on the durability of machines and equipment in operation. Metallic structures are most often surrounded by such environment which contains hydrogenous components or hydrogen itself (in chemical industry, power engineering, etc). And it leads to various types of degradation in metals (hydrogen embrittlement, hydrogen corrosion, and so on), which, in its turn, could cause catastrophic results. Ultimate strength is considered to be a representative parameter of the process of hydrogen degradation in steels. The authors cite the results of testing conducted on hydrogen-saturated specimens made of A516-55 steel which register a significant decrease in the ultimate strength. It is proposed to use a diagram which describes a fall in metal strength and transition of structural materials into their brittle states following an increase in hydrogen concentration. Discussion is made on criteria for hydrogen-saturated materials of metallic structures failing when a momentary overload occurs under default working conditions.

Стилі APA, Harvard, Vancouver, ISO та ін.

29

Ashrafriahi, Ali, Ali Seifitokaldani, and Roger Newman. "DFT Analysis of Ethanol Electro-Oxidation on Fe(110) and Fe₃c(110) and Its Correlation with the Stress Corrosion Cracking of Carbon Steel." ECS Meeting Abstracts MA2022-02, no. 10 (October 9, 2022): 694. http://dx.doi.org/10.1149/ma2022-0210694mtgabs.

Повний текст джерела

Анотація:

Stress Corrosion Cracking (SCC) of carbon steel in fuel-grade ethanol is typically intergranular in service, but it is nearly always transgranular, in short-term laboratory experiments. While this might be considered an inconvenience, it provides an important clue about the SCC mechanism. The important point is that the transgranular cracking occurs under much milder mechanical conditions than any known form of hydrogen embrittlement in ordinary carbon steel. For this and other reasons, hydrogen is not considered to be the cause of this form of SCC. Transgranular SCC of carbon steel occurs in a very particular set of environments. Anhydrous liquid ammonia, anhydrous ammonia-methanol and CO-CO2-H2O are the key systems to be considered, apart from alcohols. High-temperature water containing oxygen also causes transgranular SCC, but is a less severe environment, probably because a magnetite film imposes a compressive stress that partially opposes any embrittlement effect. In our view, the important factor connecting these examples is embrittlement by interstitials. Just as hydrogen can embrittle iron, so can nitrogen or carbon (or oxygen). The main distinction is the diffusivity of the interstitial in iron. Ammonia can be oxidized to N, and CO can be reduced to C (or, in the language of surface chemistry, this could be dissociative adsorption). Still, at ambient temperature, those interstitials can only diffuse a few nm in relevant times of seconds. But we know little about the effect of such near-surface embrittlement on the propagation of a crack, and research on such surface effects is very important. Striking mechanical and morphological similarities of the SCC of carbon steel in ethanolic media with those governed by a cleavage-like mechanism in CO-CO2 aqueous solutions prompted the investigation of the possibility of ethanol electrochemical oxidation into CO on ferrite (Fe) and cementite (Fe3C) surfaces. Density functional theory computations on (110) surfaces revealed that the catalytic activity of Fe and Fe3C through the α dehydrogenation pathway can significantly reduce the energy barrier of electro-oxidation of ethanol and production of CO to 0.575 and 0.480 eV, respectively. These first principle calculations indicate that at the anodic potentials applied during potentiostatic slow strain rate testing, ethanol electro-oxidation to CO is thermodynamically viable on carbon steel, giving further credit to the involvement of cleavage type SCC of carbon steel in ethanolic environments.

Стилі APA, Harvard, Vancouver, ISO та ін.

30

Boot, Tim, Ton (A C. ). Riemslag, Elise (T E. ). Reinton, Ping Liu, Carey L. Walters, and Vera Popovich. "In-Situ Hollow Sample Setup Design for Mechanical Characterisation of Gaseous Hydrogen Embrittlement of Pipeline Steels and Welds." Metals 11, no. 8 (August 5, 2021): 1242. http://dx.doi.org/10.3390/met11081242.

Повний текст джерела

Анотація:

This work discusses the design and demonstration of an in-situ test setup for testing pipeline steels in a high pressure gaseous hydrogen (H2) environment. A miniature hollow pipe-like tensile specimen was designed that acts as the gas containment volume during the test. Specific areas of the specimen can be forced to fracture by selective notching, as performed on the weldment. The volume of H2 used was minimised so the test can be performed safely without the need of specialised equipment. The setup is shown to be capable of characterising Hydrogen Embrittlement (HE) in steels through testing an X60 pipeline steel and its weldment. The percentage elongation (%El) of the base metal was found to be reduced by 40% when tested in 100 barg H2. Reduction of cross-sectional area (%RA) was found to decrease by 28% and 11% in the base metal and weld metal, respectively, when tested in 100 barg H2. Benchmark test were performed at 100 barg N2 pressure. SEM fractography further indicated a shift from normal ductile fracture mechanisms to a brittle transgranular (TG) quasi-cleavage (QC) type fracture that is characteristic of HE.

Стилі APA, Harvard, Vancouver, ISO та ін.

31

Li, Qing, Guangxu Cheng, Mu Qin, Yafei Wang, and Zaoxiao Zhang. "Research on Carbide Characteristics and Their Influence on the Properties of Welding Joints for 2.25Cr1Mo0.25V Steel." Materials 14, no. 4 (February 13, 2021): 891. http://dx.doi.org/10.3390/ma14040891.

Повний текст джерела

Анотація:

The carbide characteristics of 2.25Cr1Mo0.25V steel have an extremely important influence on the mechanical properties of welding joints. In addition, hydrogen resistance behavior is crucial for steel applied in hydrogenation reactors. The carbide morphology was observed by scanning electron microscopy (SEM) and the carbide microstructure was characterized by transmission electron microscopy (TEM). Tensile and impact tests were carried out and the influence of carbides on properties was studied. A hydrogen diffusion test was carried out, and the hydrogen brittleness resistance of welding metal and base metal was studied by tensile testing of hydrogenated samples to evaluate the influence of hydrogen on the mechanical properties. The research results show that the strength of the welding metal was slightly higher and the Charpy impact value was significantly lower compared to the base metal. The hydrogen embrittlement resistance of the welding metal was stronger than that of the base metal. The presence of more carbides and inclusions was the main cause of the decreased impact property and hydrogen brittleness resistance of the welding metal. These conclusions have certain reference value for designing and manufacturing hydrogenation reactors.

Стилі APA, Harvard, Vancouver, ISO та ін.

32

YAMAMOTO, Hiroki, Tetsuya UCHIMOTO, Toshiyuki TAKAGI, Hirotoshi ENOKI, and Takashi IIJIMA. "Evaluation of Phase Transition by Eddy Current Testing for Hydrogen Embrittlement of Austenitic Stainless Steel." Proceedings of Conference of Tohoku Branch 2019.54 (2019): 175. http://dx.doi.org/10.1299/jsmeth.2019.54.175.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

33

Rudomilova, Darya, Tomáš Prošek, and Gerald Luckeneder. "Techniques for investigation of hydrogen embrittlement of advanced high strength steels." Corrosion Reviews 36, no. 5 (September 25, 2018): 413–34. http://dx.doi.org/10.1515/corrrev-2017-0106.

Повний текст джерела

Анотація:

AbstractProduction volumes of advanced high strength steels (AHSS) are growing rapidly due to material and energy savings they provide in a number of application areas. In order to use their potential fully, it is necessary to minimize any danger of unexpected failures caused by hydrogen embrittlement. It is possible only if deeper understanding of underlying mechanisms is obtained through further research. Besides description of main grades of AHSS and mechanisms of HE, this paper reviews available tools for determination of hydrogen content and susceptibility to HE focusing on atmospheric conditions. Techniques such as slow strain rate testing, constant load testing, electrochemical permeation technique, scanning Kelvin probe and scanning Kelvin probe force microscopy have already been used to study the effect of hydrogen entered under atmospheric exposure conditions. Nanoindentation, hydrogen microprint technique, thermal desorption spectroscopy, Ag decoration or secondary ion mass spectrometry can be also conducted after atmospheric exposure.

Стилі APA, Harvard, Vancouver, ISO та ін.

34

Strakosova, Angelina, Michaela Roudnická, Ondřej Ekrt, Dalibor Vojtěch, and Alena Michalcová. "Hydrogen Embrittlement of the Additively Manufactured High-Strength X3NiCoMoTi 18-9-5 Maraging Steel." Materials 14, no. 17 (September 4, 2021): 5073. http://dx.doi.org/10.3390/ma14175073.

Повний текст джерела

Анотація:

The main aim of this study was to determine the susceptibility of the additively manufactured high strength X3NiCoMoTi 18-9-5 maraging steel to hydrogen embrittlement. For this purpose, samples produced by selective laser melting technology, before and after heat treatment, were used. The examined samples were electrochemically charged with hydrogen in NaCl + NH4SCN solution at a current density of 50 mA/cm2 for 24 h. The H content increased from about 1 to 15 ppm. Heat treatment did not affect the amount of H trapped in the maraging steel. Tensile testing revealed that the tensile strength of the H-charged samples was much lower than that of the uncharged samples. Moreover, the material became brittle after charging compared to the ductile as-printed and heat-treated samples with elongation values of 7% and 2%, respectively. The loss of plasticity was confirmed by fractography, which revealed transformation of the fracture surface morphology from dimple-like in the as-produced state to a brittle one with smooth facets in the H-charged state.

Стилі APA, Harvard, Vancouver, ISO та ін.

35

Parusov, E. V., I. N. Chuiko, V. A. Lutsenko, O. V. Parusov, T. N. Golubenko, O. V. Lutsenko, and A. I. Sivak. "Influence of thermal strengthening technology on variability of mechanical properties of rolled metal product." Fundamental and applied problems of ferrous metallurgy, no. 34 (2020): 202–18. http://dx.doi.org/10.52150/2522-9117-2020-34-202-218.

Повний текст джерела

Анотація:

Rebars and coiled bar have a tendency to softening over time. After holding at the room temperature the ductility of the rolled products can be partially restored due to the processes of return and relaxation and also deposition of the diffusion-movable hydrogen from the steel. The reverse hydrogen brittleness and ageing are often observed, during production of the thermally strengthening rolled products. The variability of the mechanical properties of rebars and coiled bar of 25G2S, С70D and С82D steels with different diameters has been studied. It has been shown that tendency to softening is decreases during increasing of the strength class of the rebars (steel 25G2S) and it is related to deposition of the hydrogen in different quantities. Dynamics of increase of specific elongation for rebars turns out to be maximum in the first 30 days and growing rapidly (till 4,0…4,5 % abs.) over 90...120 days, then stabilizes and practically does not change over time. After use of the accelerated cooling at the final stage of the deformation heat treatment of the coiled bar of С70D high carbon steel the variability of specific elongation and reduction of area are characterized by a significant increase of ductility indexes within 3 days after primary testing. By research of variability of mechanical properties of coiled bar of С82D steel was established that during initial testing of samples (immediately after rolling) were recorded a low values of specific elongation and reduction of area (7,6…8,4 % and 15…24 % respectively) and while the progress of embrittlement have a tends to growth with increasing diameter. After holding of the coiled bar within 48...72 hours the parameters of the ductility for all diameters of rolled products are grow to 30...34% and stabilize over time. It has been shown that variability of the mechanical properties have a direct relations with the parameters of the structure, the initial hydrogen content in the steel and with degree of deformation processing of blank continuous casting.

Стилі APA, Harvard, Vancouver, ISO та ін.

36

Horikawa, Keitaro, Hidetoshi Kobayashi, and Motohiro Kanno. "Hydrogen Evolution Behavior during Tensile Deformation in Austenitic Stainless Steels Exposed to High Compressed Hydrogen Atmospheres." Materials Science Forum 654-656 (June 2010): 2519–22. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.2519.

Повний текст джерела

Анотація:

Hydrogen embrittlement sensitivity of austenitic stainless steels, SUS316L and SUS310S exposed to high compressed hydrogen gas atmospheres was evaluated by means of a slow strain rate testing (SSRT) in air. Hydrogen evolution behavior during tensile deformation and fracture was also investigated by using a testing machine equipped with a quadrupole mass spectrometer installed in an ultrahigh vacuum chamber. When the SUS 316L specimen with hydrogen gas charging were deformed at a very slow crosshead speed of 1.67 nm/s, local deformation was promoted as compared to the specimen without hydrogen gas charging. On the other hand, no decrease of the ductility was observed in the SUS310S specimen with hydrogen gas charging even in the SSRT. In the hydrogen charged SUS316L specimen, the amount of continuous hydrogen evolution throughout deformation was much higher than that in the specimen without hydrogen gas charging. In addition, sudden hydrogen evolutions were sometimes identified in the SUS316L specimen with hydrogen gas charging during the deformation.

Стилі APA, Harvard, Vancouver, ISO та ін.

37

Li, Yunlong, Keshi Zhang, Damin Lu, and Bin Zeng. "Hydrogen-Assisted Brittle Fracture Behavior of Low Alloy 30CrMo Steel Based on the Combination of Experimental and Numerical Analyses." Materials 14, no. 13 (July 2, 2021): 3711. http://dx.doi.org/10.3390/ma14133711.

Повний текст джерела

Анотація:

Compact-tension (CT) specimens made of low alloy 30CrMo steels were hydrogen-charged, and then subjected to the fracture toughness test. The experimental results revealed that the higher crack propagation and the lower crack growth resistance (CTOD-R curve) are significantly noticeable with increasing hydrogen embrittlement (HE) indexes. Moreover, the transition in the microstructural fracture mechanism from ductile (microvoid coalescence (MVC)) without hydrogen to a mixed quasi-cleavage (QC) fracture and QC + intergranular (IG) fracture with hydrogen was observed. The hydrogen-enhanced decohesion (HEDE) mechanism was characterized as the dominant HE mechanism. According to the experimental testing, the coupled problem of stress field and hydrogen diffusion field with cohesive zone stress analysis was employed to simulate hydrogen-assisted brittle fracture behavior by using ABAQUS software. The trapezoidal traction-separation law (TSL) was adopted, and the initial TSL parameters from the best fit to the load-displacement and J-integral experimental curves without hydrogen were calibrated for the critical separation of 0.0393 mm and the cohesive strength of 2100 MPa. The HEDE was implemented through hydrogen influence in the TSL, and to estimate the initial hydrogen concentration based on matching numerical and experimental load-line displacement curves with hydrogen. The simulation results show that the general trend of the computational CTOD-R curves corresponding to initial hydrogen concentration is almost the same as that obtained from the experimental data but in full agreement, the computational CTOD values being slightly higher. Comparative analysis of numerical and experimental results shows that the coupled model can provide design and prediction to calculate hydrogen-assisted fracture behavior prior to extensive laboratory testing, provided that the material properties and properly calibrated TSL parameters are known.

Стилі APA, Harvard, Vancouver, ISO та ін.

38

Lee, Seung-Yong, Un-Bong Baek, Seung Hoon Nam, and Byoungchul Hwang. "Hydrogen Embrittlement of Two Austenitic High-Manganese Steels Using Tensile Testing under High-Pressure Gaseous Hydrogen." Korean Journal of Materials Research 26, no. 7 (July 30, 2016): 353–58. http://dx.doi.org/10.3740/mrsk.2016.26.7.353.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

39

Cauwels, Margo, Lisa Claeys, Tom Depover, and Kim Verbeken. "The hydrogen embrittlement sensitivity of duplex stainless steel with different phase fractions evaluated by in-situ mechanical testing." Frattura ed Integrità Strutturale 14, no. 51 (December 7, 2019): 449–58. http://dx.doi.org/10.3221/igf-esis.51.33.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

40

Raman, R. K. Singh, R. Javaherdashti, C. Panter, and E. V. Pereloma. "Hydrogen embrittlement of a low carbon steel during slow strain testing in chloride solutions containing sulphate reducing bacteria." Materials Science and Technology 21, no. 9 (September 2005): 1094–98. http://dx.doi.org/10.1179/174328405x51811.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

41

Fukuyama, Seiji, Lin Zhang, and Kiyoshi Yokogawa. "Development of Materials Testing Equipment in High Pressure Hydrogen and Hydrogen Environment Embrittlement of Austenitic Stainless Steels." Journal of the Japan Institute of Metals 68, no. 2 (2004): 62–65. http://dx.doi.org/10.2320/jinstmet.68.62.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

42

Matsumoto, Yu, Tomonori Miyashita, and Kenichi Takai. "Hydrogen behavior in high strength steels during various stress applications corresponding to different hydrogen embrittlement testing methods." Materials Science and Engineering: A 735 (September 2018): 61–72. http://dx.doi.org/10.1016/j.msea.2018.08.002.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

43

Oguma, Noriyasu, Naoya Sekisugi, Katsuyuki Kida, Yasuhiro Odake, and Tatsuo Sakai. "Period of Fine Granular Area Formation of Bearing Steel in Very High Cycle Fatigue Regime." Advanced Materials Research 891-892 (March 2014): 434–39. http://dx.doi.org/10.4028/www.scientific.net/amr.891-892.434.

Повний текст джерела

Анотація:

In order to examine the period of fine granular area (FGA) formation of bearing steel in very high cycle fatigue regime, rotating bending fatigue tests were carried out at the stress amplitude 1100 MPa below the fatigue limit. The tests were interrupted at the cumulative damage values ranging from 0.1 to 0.5 with an increment of 0.1 to charge hydrogen to the specimens. After the charge, the rotating bending tests were continuously carried out. The crack origin areas on all fracture surfaces were checked by a scanning electron microscope (SEM), and it was discovered that FGA was not formed in some of them. From a view point of fracture mechanics, the stress intensity factor ranges of FGA areas, ΔKFGA, were calculated by using Murakamis area model. The ΔKFGA values increase with the increase of the cumulative damage values. Furthermore, ΔKFGA values in this study were smaller than 5 MPam which was obtained from usual fatigue testing. Therefore, we conclude that the stable crack growth stage starts when the threshold stress intensity factor range decreases due to hydrogen embrittlement in the middle of formation of FGA.

Стилі APA, Harvard, Vancouver, ISO та ін.

44

OGATA, Toshio. "3502 Hydrogen environment embrittlement of stainless steels at low Temperatures by the simple testing method for hydrogen environment." Proceedings of the JSME annual meeting 2006.1 (2006): 619–20. http://dx.doi.org/10.1299/jsmemecjo.2006.1.0_619.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

45

Toribio, Jesús, Miguel Lorenzo, and Leticia Aguado. "Innovative Design of Residual Stress and Strain Distributions for Analyzing the Hydrogen Embrittlement Phenomenon in Metallic Materials." Materials 15, no. 24 (December 19, 2022): 9063. http://dx.doi.org/10.3390/ma15249063.

Повний текст джерела

Анотація:

Round-notched samples are commonly used for testing the susceptibility to hydrogen embrittlement (HE) of metallic materials. Hydrogen diffusion is influenced by the stress and strain states generated during testing. This state causes hydrogen-assisted micro-damage leading to failure that is due to HE. In this study, it is assumed that hydrogen diffusion can be controlled by modifying such residual stress and strain fields. Thus, the selection of the notch geometry to be used in the experiments becomes a key task. In this paper, different HE behaviors are analyzed in terms of the stress and strain fields obtained under diverse loading conditions (un-preloaded and preloaded causing residual stress and strains) in different notch geometries (shallow notches and deep notches). To achieve this goal, two uncoupled finite element (FE) simulations were carried out: (i) a simulation by FE of the loading sequences applied in the notched geometries for revealing the stress and strain states and (ii) a simulation of hydrogen diffusion assisted by stress and strain, for estimating the hydrogen distributions. According to results, hydrogen accumulation in shallow notches is heavily localized close to the wire surface, whereas for deep notches, hydrogen is more uniformly distributed. The residual stress and plastic strains generated by the applied preload localize maximum hydrogen concentration at deeper points than un-preloaded cases. As results, four different scenarios are established for estimating “a la carte” the HE susceptibility of pearlitic steels just combining two notch depths and the residual stress and strain caused by a preload.

Стилі APA, Harvard, Vancouver, ISO та ін.

46

Drexler, Andreas, Besim Helic, Zahra Silvayeh, Klemens Mraczek, Christof Sommitsch, and Josef Domitner. "The role of hydrogen diffusion, trapping and desorption in dual phase steels." Journal of Materials Science 57, no. 7 (January 29, 2022): 4789–805. http://dx.doi.org/10.1007/s10853-021-06830-0.

Повний текст джерела

Анотація:

AbstractHydrogen embrittlement (HE) of advanced high-strength steels is a crucial problem in the automotive industry, which may cause time-delayed failure of car body components. Practical approaches for evaluating the HE risk are often partially and contradictive in nature, because of hydrogen desorption during testing and inhomogenous hydrogen distributions in, e.g., notched samples. Therefore, the present work aims to provide fully parametrized and validated bulk diffusion models for three dual phase steels to simulate long-range chemical diffusion, trapping and hydrogen desorption from the surface. With one constant set of parameters, the models are able to predict the temperature dependency of measured Choo-Lee plots as well as the concentration dependency of measured effective diffusion coefficients. Finally, the parametrized and validated bulk diffusion models are applied for studying the role of the current density on the permeation time and the role of coatings as effective diffusion barriers. Graphical abstract

Стилі APA, Harvard, Vancouver, ISO та ін.

47

Li, Yizhe, Baoming Gong, Xiaogang Li, Caiyan Deng, and Dongpo Wang. "Specimen thickness effect on the property of hydrogen embrittlement in single edge notch tension testing of high strength pipeline steel." International Journal of Hydrogen Energy 43, no. 32 (August 2018): 15575–85. http://dx.doi.org/10.1016/j.ijhydene.2018.06.118.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

48

Castellote, M., J. Fullea, P. G. de Viedma, C. Andrade, C. Alonso, I. Llorente, X. Turrillas, et al. "Hydrogen embrittlement of high-strength steel submitted to slow strain rate testing studied by nuclear resonance reaction analysis and neutron diffraction." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 259, no. 2 (June 2007): 975–83. http://dx.doi.org/10.1016/j.nimb.2007.03.084.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

49

Brück, Sven, Bastian Blinn, Katharina Diehl, Yannick Wissing, Julian Müller, Martina Schwarz, Hans-Jürgen Christ, et al. "Analysis of Hydrogen-Induced Changes in the Cyclic Deformation Behavior of AISI 300–Series Austenitic Stainless Steels Using Cyclic Indentation Testing." Metals 11, no. 6 (June 6, 2021): 923. http://dx.doi.org/10.3390/met11060923.

Повний текст джерела

Анотація:

The locally occurring mechanisms of hydrogen embrittlement significantly influence the fatigue behavior of a material, which was shown in previous research on two different AISI 300-series austenitic stainless steels with different austenite stabilities. In this preliminary work, an enhanced fatigue crack growth as well as changes in crack initiation sites and morphology caused by hydrogen were observed. To further analyze the results obtained in this previous research, in the present work the local cyclic deformation behavior of the material volume was analyzed by using cyclic indentation testing. Moreover, these results were correlated to the local dislocation structures obtained with transmission electron microscopy (TEM) in the vicinity of fatigue cracks. The cyclic indentation tests show a decreased cyclic hardening potential as well as an increased dislocation mobility for the conditions precharged with hydrogen, which correlates to the TEM analysis, revealing courser dislocation cells in the vicinity of the fatigue crack tip. Consequently, the presented results indicate that the hydrogen enhanced localized plasticity (HELP) mechanism leads to accelerated crack growth and change in crack morphology for the materials investigated. In summary, the cyclic indentation tests show a high potential for an analysis of the effects of hydrogen on the local cyclic deformation behavior.

Стилі APA, Harvard, Vancouver, ISO та ін.

50

Álvarez, G., A. Zafra, F. J. Belzunce, and C. Rodríguez. "Hydrogen embrittlement testing procedure for the analysis of structural steels with Small Punch Tests using notched specimens." Engineering Fracture Mechanics 253 (August 2021): 107906. http://dx.doi.org/10.1016/j.engfracmech.2021.107906.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Статті в журналах з теми "Steel Hydrogen embrittlement Testing"

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями