Observation of hydrogen trapping at dislocations, grain boundaries, and precipitates

Science ◽  
2020 ◽  
Vol 367 (6474) ◽  
pp. 171-175 ◽  
Author(s):  
Yi-Sheng Chen ◽  
Hongzhou Lu ◽  
Jiangtao Liang ◽  
Alexander Rosenthal ◽  
Hongwei Liu ◽  
...  
Keyword(s):  
Hydrogen Embrittlement ◽  
Grain Boundaries ◽  
Thermal Desorption Spectroscopy ◽  
High Strength ◽  
Atom Probe ◽  
Hydrogen Trapping ◽  
Hydrogen Atoms ◽  
Multiple Length Scales ◽  
Hydrogen Retention ◽  
Defect Interactions

Hydrogen embrittlement of high-strength steel is an obstacle for using these steels in sustainable energy production. Hydrogen embrittlement involves hydrogen-defect interactions at multiple-length scales. However, the challenge of measuring the precise location of hydrogen atoms limits our understanding. Thermal desorption spectroscopy can identify hydrogen retention or trapping, but data cannot be easily linked to the relative contributions of different microstructural features. We used cryo-transfer atom probe tomography to observe hydrogen at specific microstructural features in steels. Direct observation of hydrogen at carbon-rich dislocations and grain boundaries provides validation for embrittlement models. Hydrogen observed at an incoherent interface between niobium carbides and the surrounding steel provides direct evidence that these incoherent boundaries can act as trapping sites. This information is vital for designing embrittlement-resistant steels.

Techniques for investigation of hydrogen embrittlement of advanced high strength steels

2018 ◽  
Vol 36 (5) ◽  
pp. 413-434 ◽  
Author(s):  
Darya Rudomilova ◽  
Tomáš Prošek ◽  
Gerald Luckeneder
Keyword(s):  
Hydrogen Embrittlement ◽  
Secondary Ion Mass Spectrometry ◽  
High Strength Steels ◽  
Thermal Desorption Spectroscopy ◽  
High Strength ◽  
Atmospheric Conditions ◽  
Kelvin Probe ◽  
Advanced High Strength Steels ◽  
Scanning Kelvin Probe ◽  
Atmospheric Exposure

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.

scholarly journals Improving Hydrogen Embrittlement Resistance of Hot-Stamped 1500 MPa Steel Parts That Have Undergone a Q&P Treatment by the Design of Retained Austenite and Martensite Matrix

Metals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1585
Author(s):  
Zhou Wang ◽  
Mingxin Huang
Keyword(s):  
Hydrogen Embrittlement ◽  
Retained Austenite ◽  
High Strength ◽  
Tensile Tests ◽  
Hydrogen Trapping ◽  
Dog Bone ◽  
Hot Stamped Steel ◽  
Martensite Matrix ◽  
Embrittlement Resistance ◽  
Hydrogen Embrittlement Resistance

Hydrogen embrittlement is one of the largest obstacles against the commercialisation of ultra-high strength quenching and partitioning (Q&P) steels with ultimate tensile strength over 1500 MPa, including the hot stamped steel parts that have undergone a Q&P treatment. In this work, the influence of partitioning temperature on hydrogen embrittlement of ultra-high strength Q&P steels is studied by pre-charged tensile tests with both dog-bone and notched samples. It is found that hydrogen embrittlement resistance is enhanced by the higher partitioning temperature. Then, the hydrogen embrittlement mechanism is analysed in terms of hydrogen, retained austenite, and martensite matrix. Thermal desorption analysis (TDA) shows that the hydrogen trapping properties are similar in the Q&P steels, which cannot explain the enhancement of hydrogen embrittlement resistance. On the contrary, it is found that the relatively low retained austenite stability after the higher temperature partitioning ensures more sufficient TRIP effect before hydrogen-induced fracture. Additionally, dislocation recovery and solute carbon depletion at the higher partitioning temperature can reduce the flow stress of the martensite matrix, improving its intrinsic toughness and reducing its hydrogen sensitivity, both of which result in the higher hydrogen embrittlement resistance.

Studies of SCC and Hydrogen Embrittlement of High Strength Alloys Using Fracture Mechanics Methods

2005 ◽  
Vol 482 ◽  
pp. 11-16 ◽  
Author(s):  
Wolfgang Dietzel ◽  
Michael Pfuff ◽  
Guido G. Juilfs
Keyword(s):  
Plastic Deformation ◽  
Fracture Mechanics ◽  
Hydrogen Embrittlement ◽  
Hydrogen Diffusion ◽  
High Strength Steels ◽  
High Strength ◽  
Constant Load ◽  
Rate Of Change ◽  
Extension Rate ◽  
Hydrogen Atoms

Fracture mechanics based test and evaluation techniques are used to gain insight into the phenomenon of stress corrosion cracking (SCC) and to develop guidance for avoiding or controlling SCC. Complementary to well known constant load and constant deflection test methods experiments that are based on rising load or rising displacement situations and are specified in the new ISO standard 7539 – Part 9 may be applied to achieve these goals. These are particularly suitable to study cases of SCC and hydrogen embrittlement of high strength steels, aluminium and titanium alloys and to characterise the susceptibility of these materials to environmentally assisted cracking. In addition, the data generated in such R-curve tests can be used to model the degradation of the material caused by the uptake of atomic hydrogen from the environment. This is shown for the case of a high strength structural steel (FeE 690T) where in fracture mechanics SCC tests on pre-cracked C(T) specimens a correlation between the rate of change in plastic deformation and the crack extension rate due to hydrogen embrittlement was established. The influence of plastic strain on the hydrogen diffusion was additionally studied by electrochemical permeation experiments. By modelling this diffusion based on the assumption that trapping of the hydrogen atoms takes place at trap sites which are generated by the plastic deformation, a good agreement was achieved between experimentally obtained data and model predictions.

A review of hydrogen embrittlement of martensitic advanced high-strength steels

2016 ◽  
Vol 34 (3) ◽  
pp. 153-186 ◽  
Author(s):  
Jeffrey Venezuela ◽  
Qinglong Liu ◽  
Mingxing Zhang ◽  
Qingjun Zhou ◽  
Andrej Atrens
Keyword(s):  
Hydrogen Embrittlement ◽  
High Strength Steels ◽  
High Strength ◽  
Applied Strain ◽  
Service Performance ◽  
Hydrogen Trapping ◽  
Comprehensive Understanding ◽  
Advanced High Strength Steels ◽  
Laboratory Results ◽  
Applied Strain Rate

AbstractThe martensitic advanced high-strength steels (MS-AHSS) are used to create fuel-efficient, crashworthy cars. Hydrogen embrittlement (HE) is an issue with high-strength steels; thus, the interaction of hydrogen with MS-AHSS needs to be studied. There are only a few published works on the HE of MS-AHSS. The current literature indicates that the HE susceptibility of MS-AHSS is affected by (i) the strength of the steel, (ii) the applied strain rate, (iii) the concentration of hydrogen, (iv) microstructure, (v) tempering, (vi) residual stress, (vii) fabrication route, (viii) inclusions, (ix) metallic coatings, and (x) specific precipitates. Some of the unresolved issues include (i) the correlation of laboratory results to service performance, (ii) establishing the conditions or factors that lead to a certain HE response, (iii) studying the effect of stress rate on HE, and (iv) a comprehensive understanding of hydrogen trapping in MS-AHSS.

Study of the Hydrogen Traps in a High Strength TRIP Steel by Thermal Desorption Spectroscopy

2012 ◽  
Vol 706-709 ◽  
pp. 2253-2258 ◽  
Author(s):  
Diana Pérez Escobar ◽  
Lode Duprez ◽  
Kim Verbeken ◽  
Marc Verhaege
Keyword(s):  
Grain Boundaries ◽  
Thermal Desorption ◽  
Trip Steel ◽  
Cold Deformation ◽  
Thermal Desorption Spectroscopy ◽  
High Strength ◽  
Trip Steels ◽  
Depth Study ◽  
Different Temperatures ◽  
Steel Trip700

Thermal desorption spectroscopy (TDS) is a very important tool in hydrogen related research. It allows to distinguish between the different types of microstructural hydrogen traps based on the analysis of the different temperatures at which hydrogen desorbs from the material during heating. These peak temperatures depend on the metallurgical and microstructural characteristics of the steel under investigation and provide important information on the possible mechanisms for hydrogen embrittlement (HE). In the present work, multiple TDS experiments and an in-depth study of the microstructure were performed on a TRIP steel (TRIP700) that was previously cold deformed in order to make a correlation between the microstructural features of this material, e.g. grain boundaries, dislocations, martensite formation and the peaks that became visible during TDS. The results obtained for the TRIP grade were compared with those obtained for electrolytic pure iron, which only contained a limited amount of possible trap sites such as grain boundaries and an increasing amount of dislocations due to previous application of cold deformation. Significant differences between both materials and a significant impact of the degree of cold deformation for TRIP steels were observed.

scholarly journals Chemical heterogeneity enhances hydrogen resistance in high-strength steels

2021 ◽  
Author(s):  
Binhan Sun ◽  
Wenjun Lu ◽  
Baptiste Gault ◽  
Ran Ding ◽  
Surendra Kumar Makineni ◽  
...  
Keyword(s):  
Hydrogen Embrittlement ◽  
Thermomechanical Processing ◽  
High Strength Steels ◽  
High Strength ◽  
High Dispersion ◽  
Chemical Heterogeneity ◽  
Hydrogen Trapping ◽  
Strength And Ductility ◽  
Embrittlement Resistance ◽  
Hydrogen Embrittlement Resistance

AbstractThe antagonism between strength and resistance to hydrogen embrittlement in metallic materials is an intrinsic obstacle to the design of lightweight yet reliable structural components operated in hydrogen-containing environments. Economical and scalable microstructural solutions to this challenge must be found. Here, we introduce a counterintuitive strategy to exploit the typically undesired chemical heterogeneity within the material’s microstructure that enables local enhancement of crack resistance and local hydrogen trapping. We use this approach in a manganese-containing high-strength steel and produce a high dispersion of manganese-rich zones within the microstructure. These solute-rich buffer regions allow for local micro-tuning of the phase stability, arresting hydrogen-induced microcracks and thus interrupting the percolation of hydrogen-assisted damage. This results in a superior hydrogen embrittlement resistance (better by a factor of two) without sacrificing the material’s strength and ductility. The strategy of exploiting chemical heterogeneities, rather than avoiding them, broadens the horizon for microstructure engineering via advanced thermomechanical processing.

scholarly journals Hydrogen and deuterium charging of site-specific specimen for atom probe tomography

2021 ◽  
Vol 1 ◽  
pp. 122
Author(s):  
Heena Khanchandani ◽  
Se-Ho Kim ◽  
Rama Srinivas Varanasi ◽  
TS Prithiv ◽  
Leigh T. Stephenson ◽  
...  
Keyword(s):  
Hydrogen Embrittlement ◽  
Atom Probe Tomography ◽  
High Strength Steels ◽  
High Strength ◽  
Atom Probe ◽  
Structural Defects ◽  
Future Research ◽  
Site Specific ◽  
Modelling Studies ◽  
Underlying Mechanisms

Hydrogen embrittlement can cause a dramatic deterioration of the mechanical properties of high-strength metallic materials. Despite decades of experimental and modelling studies, the exact underlying mechanisms behind hydrogen embrittlement remain elusive. To unlock understanding of the mechanism and thereby help mitigate the influence of hydrogen and the associated embrittlement, it is essential to examine the interactions of hydrogen with structural defects such as grain boundaries, dislocations and stacking faults. Atom probe tomography (APT) can, in principle, analyse hydrogen located specifically at such microstructural features but faces strong challenges when it comes to charging specimens with hydrogen or deuterium. Here, we describe three different workflows enabling hydrogen/deuterium charging of site-specific APT specimens: namely cathodic, plasma and gas charging. We discuss in detail the caveats of the different approaches in order to help future research efforts and facilitate further studies of hydrogen in metals. Our study demonstrates successful cathodic and gas charging, with the latter being more promising for the analysis of the high-strength steels at the core of our work.

scholarly journals Nanostructure Characteristics of Al3Sc1−xZrx Nanoparticles and Their Effects on Mechanical Property and SCC Behavior of Al–Zn–Mg Alloys

Materials ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1909
Author(s):  
Ying Deng ◽  
Ziang Yang ◽  
Guo Zhang
Keyword(s):  
Mechanical Property ◽  
Grain Boundaries ◽  
Dissolution Kinetics ◽  
Lattice Misfit ◽  
High Strength ◽  
Atom Probe ◽  
Dark Field ◽  
Mg Alloys ◽  
High Angle ◽  
Scanning Transmission

The Nanostructure characteristics of Al3Sc1−xZrx nanoparticles and their effects on the mechanical properties and stress corrosion cracking (SCC) behavior of Al–Zn–Mg alloys were investigated by 3D atom probe analyses, high-angle annular-dark-field scanning transmission electron microscopy methods, electron back scattered diffraction techniques, electrochemical measurements, slow strain rate tests and quantitative calculations. The results show that adding small amounts of scandium (0.10 percent by weight) and zirconium into Al–Zn–Mg extrusion bars can precipitate Al3Sc1−xZrx nanoparticles with a number density of (7.80 ± 3.83) × 1021 per cubic meter. Those particles, with a low lattice misfit with matrix (1.14 ± 0.03 percent) and stable core-shell L12-nanostructure in aged Al–Zn–Mg alloys, can increase the yield strength by 161 ± 7 MPa via strong Orowan strengthening (the theoretical calculated value is 159 MPa) and weak Hall-Petch strengthening (the theoretical calculated value is 6 MPa). Moreover, Al3Sc1−xZrx nanoparticles can change the fracture mechanism of alloys in 3.5% NaCl solution from intergranular cracks to transgranular failure, and decrease the proportion of high-angle grain boundaries from 87% to 31%, thus reducing the microchemistry differences around the grain boundaries and anodic dissolution kinetics, and improving intergranular SCC resistance and ductility. This study offers a new approach to the simultaneous improvement in mechanical property and corrosion performance of high strength alloys.

Research of Hydrogen Atom Penetration during the Phosphorization Process of High-Strength Steel

2014 ◽  
Vol 540 ◽  
pp. 35-38
Author(s):  
Yu Su Song ◽  
Li Qing Zhou ◽  
Guang Zhe Chu
Keyword(s):  
Hydrogen Atom ◽  
Hydrogen Embrittlement ◽  
Metal Surface ◽  
High Strength Steel ◽  
Steel Surface ◽  
Hydrogen Permeation ◽  
High Strength ◽  
Hydrogen Gas ◽  
Hydrogen Atoms ◽  
Permeation Experiment

The hydrogen residued process of the High-strength steel surface during the phosphorization process was studied. By the hydrogen permeation experiment, that penetration speed of the hydrogen residued in the metal surface were measured. The result of shows:the more hydrogen gas generated in the process of phosphorization,the more hydrogen atom inside the metal. That means the hydrogen embrittlement criticality of the High-strength steel were more fearful。Dense phosphorizing film always block hydrogen atoms to penetrate into the metal,So that cuold to reduce the hydrogen embrittlement extend of the steel in phosphorization.

Sign in / Sign up

Export Citation Format

Share Document