Hydrogen Compatibility Research Articles

An Experimental Study on High-Pressure Hydrogen Compatibility of Rubber Seals at FCV Refuelling Receptacles

A method is proposed to test the sensitivity of high-pressure hydrogen compatibility of rubber O-ring seals at FCV refuelling receptacles based on a long-term high-pressure pure hydrogen full-immersion environment testing, in combination with such Chinese standards as the determination of the effect of liquids of rubber and FCV refuelling receptables. Through an aging property test system, the high-pressure pure hydrogen full-immersion testing is conducted for 5 groups of rubber O-ring seals to be measured. Before and after the testing, an electronic balance is used to measure the mass of the rubber O-ring seals, obtaining changes in mass and volume. At last, on the basis of the changes, the sensitivity of the seals of various models and in diverse experimental groups to the high-pressure hydrogen compatibility is obtained through our analysis.

Hydrogen compatibility of a nitrogen-added metastable austenitic stainless steel

Hydrogen compatibility of a nitrogen-added metastable austenitic stainless steel

In situ friction and wear behavior of rubber materials incorporating various fillers and/or a plasticizer in high-pressure hydrogen

Polymers are used routinely for equipment and infrastructure in hydrogen vehicle refueling stations, but significant gaps remain in understanding their hydrogen compatibility. The tribological properties of these materials in a high-pressure hydrogen environment is important in preventing component failure and the need for frequent replacement. We present in situ tribological studies on model rubbers, which include common fillers and plasticizer, using an in situ tribometer developed previously. Results suggest a clear, yet complicated, combined effect of the high-pressure hydrogen and the additives on the tribological performance of the chosen materials, as compared to matching experiments performed in ambient air. We find that the additives improved wear resistance in EPDM but deteriorated that in NBR due to disparate additive-polymer interactions.

H-Mat hydrogen compatibility of polymers and elastomers

The H2@Scale program of the U.S. Department of Energy (DOE) Fuel Cell Technologies Office is supporting work on the hydrogen compatibility of polymers to improve the durability and reliability of materials for hydrogen infrastructure. The hydrogen compatibility program (H-Mat) seeks “to address the challenges of hydrogen degradation by elucidating the mechanisms of hydrogen-materials interactions with the goal of providing science-based strategies to design materials, (micro)structures, and morphology with improved resistance to hydrogen degradation.” This research has observed interactions of hydrogen and pressure with model rubber-material compounds resulting in volume change and compression-set differences in the materials. The materials were investigated using helium-ion microscopy (HeIM), which revealed significant morphological changes in the plasticizer-incorporating compounds after exposure, as evidenced by time-of-flight secondary ion mass spectrometry. Additional studies using transmission electron microscopy and nuclear magnetic resonance were performed to correlate morphological change to potential chemical change in the materials.

Stacking Fault Energy Based Alloy Screening for Hydrogen Compatibility

The selection of austenitic stainless steels for hydrogen service is challenging since there are few intrinsic metrics that relate alloy composition to hydrogen degradation. One such metric, presented here, is intrinsic stacking fault energy (SFE). This work reviews the exiting literature to use estimated intrinsic SFE values, calculated with a sub-regular solution thermodynamic model, to compare the retention of tensile ductility of γ-austenitic stainless steels in the presence of hydrogen. The goal is to demonstrate SFE as a metric to screen γ-austenitic stainless steels that use diverse alloying strategies for hydrogen compatibility. A transition in the tensile reduction of area of both 300-series and manganese-stabilized stainless steels is observed at a calculated stacking fault energy of approximately 39 mJ m−2, below which pronounced hydrogen degradation on tensile ductility is observed. Calculated intrinsic stacking fault energy is demonstrated as a high-throughput screening metric for a diverse range of austenitic stainless steel compositions with regard to hydrogen compatibility.

Hydrogen distribution of hydrogen-charged nickel analyzed via hardness test and secondary ion mass spectrometry

The hydrogen compatibility of metallic materials is often evaluated by conducting tensile tests of H-charged specimens in air or inert gas at ambient temperature; however, it is not clear whether the H distribution calculated with hydrogen diffusivity under a diffusion-controlled process is consistent with the actual distribution. This study estimated the hydrogen distribution in a H-charged nickel maintained in air at ambient temperature for a few months after exposure to hydrogen gas by using the Vickers hardness test and secondary ion mass spectrometry. Both methods provided similar H distributions, which were fitted by the solution of a diffusion equation under a diffusion-controlled process, and the hydrogen diffusivity was also determined. The estimated H distributions were successfully fitted by the solution of the diffusion equation, and the determined hydrogen diffusivity of nickel was consistent with literature data, indicating that the calculated H distribution reproduced the actual one.

An ultrasensitive hydrogen fuse based on a single Pd break junction

The development of hydrogen compatibility is crucial for its being a new key energy source. A study of hydrogen fuse based on Pd break junction method is presented to explore the limit of sensitivity. The critical part of this device was fabricated from a Pd nanowire electrode (80 ± 20 nm) made by electron beam lithography (EBL) method. Subsequent electromigration technique is utilized to develop a controllable break junction on the nanowire (1–2 nm). This device shows reversible response cycles of hydrogen in an ultralow pressure range below 0.1±0.002 Pa and fuse-like response above 10 Pa at room temperature. The results show that the relationship between quantum conductance with hydrogen pressure was kept linear because of hydrogen absorption induced expansion of break junction. When the expansion exceeds the threshold value, the break junction gap is closed and becoming conductive. This method opens up a possibility to detect hydrogen under ultralow partial pressure.

(Invited) H-Mat: Enhancing the Durability and Affordability of Metals and Polymers in Hydrogen Service

The H-Mat national laboratory consortium is conducting cross-cutting, foundational R&D to enhance the durability of key polymers and metals in hydrogen service. Technologies utilized in hydrogen service commonly face stresses that influence materials compatibility, such as cryogenic temperatures, fatigue loading, and corrosive environments. Industries in which hydrogen compatibility can heavily influence materials selection are diverse, and include fuel cell electric vehicles (FCEVs), nuclear energy technologies, oil & gas sectors, and vehicle lightweighting applications. H-Mat R&D aims to enhance fundamental understanding of materials’ behavior in hydrogen, with a current focus on materials used onboard FCEVs and at fueling stations. Key research thrusts include: 1) development of novel experimental polymers with enhanced durability in hydrogen pressure cycles, 2) microstructural engineering to enhance the fracture toughness of high-strength steels in hydrogen, 3) development of higher-fidelity predictions of crack initiation in steels in hydrogen service, and 4) evaluation of the effects of moisture on hydrogen induced degradation in aluminum alloys. These R&D thrusts are targeted to enhance durability of hydrogen seals by 50%, fracture resistance of pressure vessel steels by 50%, and life of pressure vessels by 50%. H-Mat is led by Sandia National Laboratories and Pacific Northwest National Laboratory, with participation from Oak Ridge National Laboratory, Savannah River National Laboratory, and Argonne National Laboratory. Members of industry and academia are encouraged to engage with the consortium through cooperative research and development agreements (CRADAs) and funding opportunity announcement (FOA) awards. For more information, please see: https://www.energy.gov/eere/fuelcells/h-mat-hydrogen-materials-consortium

Development of regulations, codes and standards on composite tanks for on-board gaseous hydrogen storage

Composite tanks for on-board gaseous hydrogen storage is one of key parts of the hydrogen fuel cell vehicle. Regulations, codes and standards (RC & S) are conducive to overcoming technological barriers to commercialization. This paper reviews the development of RC & S on composite tanks for on-board gaseous hydrogen storage and addresses their highlights on technical requirements. First, an overview of RC & S for composite tanks is introduced. Then, a comparative study on technical requirements of RC & S including service conditions, design requirements, materials, manufacture, qualification tests and management is presented. Finally, several major differences in RC & S, i.e., tank classification in ISO 19881 and penetration test method are discussed. Some issues for further research, such as initial burst pressure, material hydrogen compatibility and periodic inspection methods are proposed.

A REVIEW OF HYDROGEN STORAGE SYSTEMS BASED ON BORON AND ITS COMPOUNDS

This work is a survey of utilization of boron for hydrogen storage. Boron is a promising element for hydrogen storage with its chemical hydrides and nanostructural forms. It is also used as an additive in nickel metal hydride battery systems to enhance hydrogen compatibility and performance. This present study will be a brief summary of hydrogen storage technology in general and focus on possible uses of boron and its compounds.

Material performance of age-hardened beryllium–copper alloy, CDA-C17200, in a high-pressure, gaseous hydrogen environment

In order to develop safer and more energy-efficient, hydrogen pre-cooling systems for use in hydrogen refueling stations, it is necessary to identify a high-strength metallic material with greater thermal conductivity and lower susceptibility to hydrogen embrittlement, as compared with ordinary, stable austenitic stainless steels. To accomplish this task, the hydrogen compatibility of a precipitation-hardened, high-strength, copper-based alloy was investigated by slow-strain-rate tensile (SSRT), fatigue-life, fatigue-crack-growth (FCG) and fracture toughness tests in 115-MPa hydrogen gas at room temperature. The hydrogen solubility and diffusivity of the alloy were also determined. The hydrogen solubility of the alloy was two or three orders of magnitude lower than that of austenitic stainless steels. The alloy also demonstrated absolutely no hydrogen-induced degradation of its strength properties, a factor which could contribute to the reduction of costs related to the construction and maintenance of hydrogen refueling stations, owing to the downsizing and improved cooling performance of the pre-cooling systems.

Evaluation test of hydrogen compatibility and low temperature toughness of high-strength material for hydrogen refueling station hiring cryopump system

Evaluation test of hydrogen compatibility and low temperature toughness of high-strength material for hydrogen refueling station hiring cryopump system

Overview of the DOE hydrogen safety, codes and standards program, part 3: Advances in research and development to enhance the scientific basis for hydrogen regulations, codes and standards

Hydrogen fuels are being deployed around the world as an alternative to traditional petrol and battery technologies. As with all fuels, regulations, codes and standards are a necessary component of the safe deployment of hydrogen technologies. There has been a focused effort in the international hydrogen community to develop codes and standards based on strong scientific principles to accommodate the relatively rapid deployment of hydrogen-energy systems. The need for science-based codes and standards has revealed the need to advance our scientific understanding of hydrogen in engineering environments. This brief review describes research and development activities with emphasis on scientific advances that have aided the advancement of hydrogen regulations, codes and standards for hydrogen technologies in four key areas: (1) the physics of high-pressure hydrogen releases (called hydrogen behavior); (2) quantitative risk assessment; (3) hydrogen compatibility of materials; and (4) hydrogen fuel quality.

Determination of hydrogen compatibility for solution-treated austenitic stainless steels based on a newly proposed nickel-equivalent equation

The nickel-equivalent equation for the materials selection of solution-treated austenitic stainless steels in present Japanese regulations does not consider nitrogen, which can improve resistance to hydrogen embrittlement. For the authorization of various austenitic stainless steels for use in high-pressure hydrogen gas and based on investigations of eight types of solution-treated austenitic stainless steels, this paper presented a newly proposed nickel-equivalent equation considering nitrogen. After tensile testing to the true strain ε of 0.3 in air at both room temperature (RT) and 228 K, the strain-induced martensite content VM was measured by a saturation magnetization technique; the VM correlated well with the proposed nickel-equivalent equation. For slow strain rate tensile (SSRT) testing in hydrogen gas at RT, the relative reduction in area (RRA) was consistently lower with increased VM for ε = 0.3 at 228 K. This suggests that the austenitic phase stability is crucial in determining the RRA of the present austenitic stainless steels and the RRA was successfully quantified by the proposed equation.

Criteria for determining hydrogen compatibility and the mechanisms for hydrogen-assisted, surface crack growth in austenitic stainless steels

To establish novel criteria for determining the hydrogen compatibility of austenitic stainless steels, as well as to elucidate the mechanisms for hydrogen-assisted surface crack growth (HASCG), slow strain rate tensile (SSRT), elasto-plastic fracture toughness (JIC), fatigue crack growth and fatigue life tests were performed on Types 304, 316 and 316L steels in high-pressure hydrogen gas. As a criterion for the use of austenitic stainless steels with lower austenitic stability in hydrogen gas, a reduction in area (RA) in hydrogen gas, φH⩾57%, or a relative reduction in area, RRA⩾0.68, is proposed to ensure that there is no degradation in tensile strength by hydrogen. Observation of fracture surface morphologies and crack growth behaviours demonstrated that, in high-pressure hydrogen gas, SSRT surface crack grew via the same mechanism as for JIC crack and fatigue crack, i.e., these cracks successively grew with a sharp shape under the loading process, due to a localized slip deformation near the crack tip. Based on the elucidated HASCG mechanism, total elongation in hydrogen gas, δH⩾10%, or, φH⩾10%, is also introduced as another criterion.

Hydrogen compatibility of austenitic stainless steel tubing and orbital tube welds

Refueling infrastructure for use in gaseous hydrogen powered vehicles requires extensive manifolding for delivering the hydrogen from the stationary fuel storage at the refueling station to the vehicle as well as from the mobile storage on the vehicle to the fuel cell or combustion engine. Manifolds for gas handling often use welded construction (as opposed to compression fittings) to minimize gas leaks. Therefore, it is important to understand the effects of hydrogen on tubing and tubing welds. This paper provides a brief overview of on-going studies on the effects of hydrogen precharging on the tensile properties of austenitic stainless tubing and orbital tube welds.

Development of methods for evaluating hydrogen compatibility and suitability

The embrittlement of metals exposed to hydrogen environments is well documented. With the deployment of hydrogen fuel cell vehicles in the consumer sector, there is a need to improve the engineering basis for the selection of materials of construction for equipment that stores and distributes high-pressure gaseous hydrogen. This brief overview summarizes publicly available guidance for evaluating materials compatibility with high-pressure gaseous hydrogen. Additionally, a new standard for measuring engineering data in gaseous hydrogen and evaluating materials suitability for service in gaseous hydrogen is introduced: the CHMC1 standard provides a general framework for qualifying materials for hydrogen service. The CHCM1 standard is unique in its broad scope and performance-based strategy for quantitatively assessing materials in their service environment and for the intended structural requirements.

Web-based resources enhance hydrogen safety knowledge

The U.S. Department of Energy's Fuel Cell Technologies Program addresses key technical challenges and institutional barriers facing the development and deployment of hydrogen and fuel cell technologies with the goal of decreasing dependence on oil, reducing carbon emissions and enabling reliable power generation. The Safety, Codes & Standards program area seeks to develop and implement the practices and procedures that will ensure safety in the operation, handling and use of hydrogen and hydrogen systems for all projects and utilize these practices and lessons learned to promote the safe use of hydrogen. Enabling the development of codes and standards for the safe use of hydrogen in energy applications and facilitating the development and harmonization of international codes and standards are integral to this work.Web-based resources play a key role in reaching, educating and informing stakeholders whose contributions will help enable the deployment of new hydrogen and fuel cell technologies. This paper surveys eight web-based tools, each targeted to a specific stakeholder audience, that are integral resources for information on hydrogen-related safety, codes and standards work in the Fuel Cell Technologies Program.•Hydrogen Incident Reporting and Lessons Learned (http://h2incidents.org)•Hydrogen Safety Best Practices (http://h2bestpractices.org)•Hydrogen Safety Bibliographic Database (http://www.hydrogen.energy.gov/biblio_database.html)•Introduction to Hydrogen Safety for First Responders (http://www.hydrogen.energy.gov/firstresponders.html)•Introduction to Hydrogen for Code Officials (http://www.hydrogen.energy.gov/training/code_official_training/)•Permitting Hydrogen Facilities (http://www.hydrogen.energy.gov/permitting/)•Safety Training for Researchers (http://www.h2labsafety.org/)•Technical Reference for Hydrogen Compatibility of Materials (http://www.sandia.gov/matlsTechRef/)The development and use of each safety knowledge tool is described.

Effect of laser peening on the hydrogen compatibility of corrosion-resistant nickel alloy

Laser-peening surface treatments have demonstrated benefits for improving resistance to stress-corrosion cracking and extension of fatigue lifetimes. The effects of laser peening on hydrogen compatibility of structural metals have not been documented. In this study, annealed and laser-peened alloy 22 (corrosion-resistant nickel-base alloy) is thermally precharged with hydrogen and tested in tension. Laser peening is found to have no significant effect on the solubility of hydrogen in alloy 22 and enhances hydrogen-assisted fracture.

Toughness and hydrogen compatibility of austenitic stainless steel welds at cryogenic temperatures

A wide range of TIG welds of austenitic stainless steels and filler materials were investigated with respect to their microstructure and cryogenic toughness. Depending on the combination of base and filler material the resulting structure of the weld seam can show either long cross-sectional δ -ferrite dendrites, isolated δ -ferrite islands or no δ -ferrite at all (fully austenitic). The δ -ferrite content varied in a range of 0–12%. An overall correlation between the δ -ferrite content and the Charpy V toughness measured at - 269 ∘ C could not be found. In all cases the toughness values were greater than 40 J / cm 2 at - 269 ∘ C . The presence of δ -ferrite did not lead to the formation of martensite upon cooling. Charpy V testing at - 269 ∘ C did not show a significant reduction in toughness compared to testing at - 196 ∘ C . Using Ni-based fillers can lead to localized hydrogen embrittlement.