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Kim Verbeken - One of the best experts on this subject based on the ideXlab platform.

  • Thermal Desorption Spectroscopy evaluation of hydrogen-induced damage and deformation-induced defects
    Materials Science and Technology, 2020
    Co-Authors: Aurélie Laureys, Lisa Claeys, Margot Pinson, Tom Depover, Kim Verbeken
    Abstract:

    Thermal Desorption Spectroscopy (TDS) was performed on ultra-low carbon (ULC) steel with various degrees of hydrogen-induced damage and deformation-induced defects. First, the extent to which hydro...

  • Evaluation of blistered and cold deformed ULC steel with melt extraction and Thermal Desorption Spectroscopy
    Procedia Structural Integrity, 2018
    Co-Authors: Aurélie Laureys, Lisa Claeys, Margot Pinson, Tom Depover, Kim Verbeken
    Abstract:

    Abstract Hydrogen characterization techniques like melt extraction and Thermal Desorption Spectroscopy (TDS) are useful tools in order to evaluate and understand the interaction between hydrogen and metals. These two techniques are used here on cold deformed ultra-low carbon (ULC) steel with and without hydrogen induced damage. The material is charged electrochemically in order to induce varying amounts of hydrogen and variable degrees of hydrogen induced damage. The aim of this work is to evaluate to which extent the hydrogen induced damage would manifest itself in melt extraction and TDS measurements.

  • The hydrogen trapping ability of TiC and V4C3 by Thermal Desorption Spectroscopy and permeation experiments
    Procedia Structural Integrity, 2018
    Co-Authors: Tom Depover, E. Van Den Eeckhout, Kim Verbeken
    Abstract:

    Abstract Hydrogen (H) presence in metals is detrimental as unpredictable failure might occur. Recent developments in material’s design indicated that microstructural features such as precipitates play an essential role in potentially increasing the resistance against H induced failure. This work evaluates the H trapping characteristics for TiC and V4C3 by Thermal Desorption Spectroscopy and permeation experiments. Two microstructural conditions are compared: as quenched vs. quenched and tempered, in which the carbides are introduced. The tempered induced precipitates are able to deeply trap a significant amount of H, which decreases the H diffusivity in the materials and removes some of the detrimental H from the microstructure. For microstructural design purposes, it is important to know the position of H. Here, H is demonstrated to be trapped at the carbide/matrix interface by modifying the tempering treatment.

  • Thermal Desorption Spectroscopy Evaluation of the Hydrogen-Trapping Capacity of NbC and NbN Precipitates
    Metallurgical and Materials Transactions A, 2014
    Co-Authors: Elien Wallaert, Tom Depover, Muhammad Arafin, Kim Verbeken
    Abstract:

    In the current study, ferritic steels containing NbC or NbN precipitates were investigated. The materials were subjected to various heat treatments, giving rise to different precipitate size distributions as determined by transmission electron microscopy. Both NbC and NbN precipitates act as hydrogen traps. The steels were hydrogen charged both electrochemically and/or from the gaseous hydrogen source, followed by multiple Thermal Desorption Spectroscopy (TDS) measurements. Electrochemical charging gave rise to a low-temperature peak [323 K to 523 K (50 °C to 250 °C)], originating from the hydrogen trapped near grain boundaries, with activation energy ranging between 24 and 33 kJ/mol, and at small NbC (39 to 48 kJ/mol) or NbN precipitates (23 to 24 kJ/mol). Gaseous charging caused a high-temperature TDS peak [723 K to 923 K (450 °C to 650 °C)], which was attributed to the presence of incoherent precipitates. The activation energy for NbC precipitates, charged in a hydrogen atmosphere, ranged between 63 and 68 kJ/mol and between 100 and 143 kJ/mol for NbN precipitates.

  • Thermal Desorption Spectroscopy study of the interaction of hydrogen with TiC precipitates
    Metals and Materials International, 2013
    Co-Authors: D. Pérez Escobar, L. Duprez, Andrej Atrens, Elien Wallaert, Kim Verbeken
    Abstract:

    Thermal Desorption Spectroscopy (TDS) was used to study hydrogen-trap interactions for an experimental steel (0.025 wt%C-0.09%Ti). After lab processing, the microstructure consisted of small (∼20 μm) ferrite grains containing nanometer TiC precipitates. After hot and cold rolling, the material contained some hydrogen (originated from the hot rolling) in irreversible traps, the TiC precipitates. After annealing in hydrogen, the TDS spectra consisted of a high temperature peak, attributed to irreversible trapping by TiC precipitates. Annealing slightly increased the TiC precipitate size. Both the peak temperature and peak area increased with increasing annealing temperature. The increase in peak area occurred together with the increase in TiC precipitate size. The TDS spectra for samples annealed at 800 °C, and electrochemically charged, contained (i) a low temperature peak which decreased in height with increasing Desorption time, and (ii) a high temperature peak that did not change significantly with Desorption time, and was similar to those after gaseous charging. The low temperature peak was attributed to reversible traps such as grain boundaries, whereas the high temperature peak was attributed to irreversible trapping by TiC precipitates. The high temperature TDS peak was composed of constituent peaks with essentially the same activation energy of 145 kJ/mol.

E. Abramov - One of the best experts on this subject based on the ideXlab platform.

  • Thermal Desorption Spectroscopy tds application in quantitative study of hydrogen evolution and trapping in crystalline and non crystalline materials
    Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2007
    Co-Authors: E Talgutelmacher, Dan Eliezer, E. Abramov
    Abstract:

    Thermal Desorption Spectroscopy is a very sensitive and accurate technique for studying hydrogen's diffusion and trapping processes in crystalline and non-crystalline materials. The technique involves accurate measurement of the Desorption rate of gas atoms, soluted or trapped in the material, while heating the sample at a known rate. This paper reviews the Thermal Desorption Spectroscopy (TDS) applications in quantitative studies of hydrogen trapping and release behavior in different crystalline and non-crystalline materials. It begins with a brief overview of the physical nature of hydrogen trapping and continues with a discussion on the origins of interactions between a hydrogen atom and a trap site. Based on the simple analytical model of Lee and Lee, some examples of the assessment of comprehensive properties of hydrogen evolution and trapping in different crystalline and non-crystalline materials by means of TDS are shown and discussed in detail.

  • Thermal Desorption Spectroscopy (TDS)- : Application in quantitative study of hydrogen evolution and trapping in crystalline and non-crystalline materials
    Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2006
    Co-Authors: E. Tal-gutelmacher, Dan Eliezer, E. Abramov
    Abstract:

    Thermal Desorption Spectroscopy is a very sensitive and accurate technique for studying hydrogen's diffusion and trapping processes in crystalline and non-crystalline materials. The technique involves accurate measurement of the Desorption rate of gas atoms, soluted or trapped in the material, while heating the sample at a known rate. This paper reviews the Thermal Desorption Spectroscopy (TDS) applications in quantitative studies of hydrogen trapping and release behavior in different crystalline and non-crystalline materials. It begins with a brief overview of the physical nature of hydrogen trapping and continues with a discussion on the origins of interactions between a hydrogen atom and a trap site. Based on the simple analytical model of Lee and Lee, some examples of the assessment of comprehensive properties of hydrogen evolution and trapping in different crystalline and non-crystalline materials by means of TDS are shown and discussed in detail.

Gabriel Meyer - One of the best experts on this subject based on the ideXlab platform.

  • Thermal Desorption Spectroscopy (TDS) method for hydrogen Desorption characterization (I): theoretical aspects
    Journal of Alloys and Compounds, 2001
    Co-Authors: Facundo J. Castro, Gabriel Meyer
    Abstract:

    Abstract We present a theoretical study of Thermal Desorption Spectroscopy applied to the characterization of hydrogen Desorption kinetics from hydride forming materials. We propose a model that considers bulk and surface processes during Desorption in the solid solution+hydride field of a metal–hydrogen system. We consider as possible rate limiting steps: diffusion, phase transformation, bulk to surface passage and two-atom recombination on the surface of the sample.

  • A novel Thermal Desorption Spectroscopy apparatus
    Review of Scientific Instruments, 2000
    Co-Authors: Facundo J. Castro, Gabriel Meyer
    Abstract:

    We present a new experimental setup designed to perform measurements of Thermal Desorption Spectroscopy of hydrogen released from metallic samples. The distinctive features of the proposed arrangement are a compact reactor and the use of a mass flow meter to measure the flux of gas desorbed from the sample. A complete set of hydrogen Desorption spectra from Pd samples has been recorded to test the equipment. The spectra show very good reproducibility, a high signal-to-noise ratio, and agree very well with results reported in the literature obtained using more sophisticated equipment. These features encourage the use of this low cost setup to perform a fast and reliable characterization of the processes controling hydrogen Desorption from metallic compounds.

  • Bulk effects in Thermal Desorption Spectroscopy
    The Journal of Chemical Physics, 1998
    Co-Authors: Facundo J. Castro, Alejandro D. Sánchez, Gabriel Meyer
    Abstract:

    In this work we analyze Thermal Desorption Spectroscopy (TDS) experiments of gases considering simultaneously atomic diffusion in the bulk and recombinative reaction on the surface of a solid sample. We perform computer simulations in a three-dimensional cubic lattice, and compare the simulated spectra with numerical results from a simple reaction-diffusion model, and analytical results from models for the fast diffusion and fast reaction regimes. We analyze the effects on the spectra of each relevant parameter: diffusivity, reaction coefficient, heating rate, initial concentration of particles and sample size. We also develop a rate-limiting step identification procedure based on the analysis of peak position as a function of initial concentration. This last procedure applied to the simulations and to experimental TDS spectra produces very good results.

B. Jonsson - One of the best experts on this subject based on the ideXlab platform.

Marc Verhaege - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of hydrogen trapping in high strength steels by Thermal Desorption Spectroscopy
    Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2012
    Co-Authors: Perez D Escobar, Kim Verbeken, L. Duprez, Marc Verhaege
    Abstract:

    Abstract High strength steels are materials of considerable interest and are increasingly used but appear to be more prone to hydrogen embrittlement (HE). In this work, four high strength steels and a pure iron, as a reference material, were studied by Thermal Desorption Spectroscopy (TDS) in order to evaluate hydrogen trapping in these materials and to correlate it to the observed response of these materials to the previously evaluated effect of hydrogen on their mechanical properties. It was found that the materials which display a rather fast and significant ductility loss during hydrogen charged tensile testing contained a higher amount of diffusible hydrogen after charging. The activation energies for the peaks present in the TDS spectra were calculated for all materials and indicated that the activation energies for all low temperature peaks are pretty similar.

  • On the Methodology of Thermal Desorption Spectroscopy to Evaluate Hydrogen Embrittlement
    Materials Science Forum, 2012
    Co-Authors: Diana Maria Perez Escobar, Kim Verbeken, L. Duprez, Marc Verhaege
    Abstract:

    Thermal Desorption Spectroscopy (TDS) is a very important tool in hydrogen embrittlement (HE) related research and has been applied on many different materials over the last decades in order to improve knowledge on the HE phenomenon. TDS provides the opportunity to distinguish between different types of hydrogen traps based on the analysis of a spectrum with different peak temperatures each corresponding to hydrogen Desorption from a specific trap. These peak temperatures, and consequently the different traps in a material, arise from the various microstructural characteristics of the material. However, TDS results are also influenced by many other parameters, such as the sample surface preparation, the electrolytes used for hydrogen charging, sample geometry, charging time, current density, charging temperature. Even though the use of Thermal Desorption to evaluate hydrogen-metal interactions has increased over the past years, a careful evaluation of the effect of these other parameters was not yet performed. In this work, the impact of some of the above mentioned parameters was studied. It was demonstrated that the sample geometry, the surface roughness, and the initial total pressure of the TDS chamber influenced significantly the obtained TDS spectrum.