The Experts below are selected from a list of 21963 Experts worldwide ranked by ideXlab platform
Kim Verbeken - One of the best experts on this subject based on the ideXlab platform.
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effect of hydrogen charging on the mechanical properties of advanced High Strength Steels
International Journal of Hydrogen Energy, 2014Co-Authors: Tom Depover, Perez D Escobar, Elien Wallaert, Z Zermout, Kim VerbekenAbstract:Abstract The present work investigates the influence of hydrogen on the mechanical properties of four multiphase High Strength Steels by means of tensile tests on notched samples. This was done by performing mechanical tests on both hydrogen charged and uncharged specimens at a cross-head displacement speed of 5 mm/min. A considerable hydrogen influence was observed, as the ductility dropped by 8–60%. In order to demonstrate the influence of diffusible hydrogen, some parameters in the experimental set-up were varied. After tensile tests, fractography was performed. It was found that hydrogen charging caused a change from ductile to transgranular cleavage failure near the notch with a transition zone to a fracture surface with ductile features near the centre.
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evaluation of hydrogen trapping in High Strength Steels by thermal desorption spectroscopy
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2012Co-Authors: Perez D Escobar, Kim Verbeken, L. Duprez, Marc VerhaegeAbstract: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.
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Advanced High Strength Steels for automotive industry
Revista De Metalurgia, 2012Co-Authors: J. Galán, Kim Verbeken, Ludovic Samek, Patricia Verleysen, Yvan HoubaertAbstract:The car industry is facing pressure because of the growing demand for more fuel-efficient passenger cars. In order to limit energy consumption and air pollution the weight of the carbody has to be reduced. At the same time, High levels of safety have to be guaranteed. In this situation, the choice of material becomes a key decision in car design. As a response to the requirements of the automotive sector, High Strength Steels and advanced High Strength Steels have been developed by the steel industry. These modern steel grades offer an excellent balance of low cost, light weight and mechanical properties.
Kaneaki Tsuzaki - One of the best experts on this subject based on the ideXlab platform.
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studies of evaluation of hydrogen embrittlement property of High Strength Steels with consideration of the effect of atmospheric corrosion
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2013Co-Authors: Eiji Akiyama, Zuogui Zhang, Songjie Li, Maoqiu Wang, Yuuji Kimura, Kaneaki TsuzakiAbstract:Hydrogen embrittlement of High-Strength Steels was investigated by using slow strain rate test (SSRT) of circumferentially notched round bar specimens after hydrogen precharging. On top of that, cyclic corrosion tests (CCT) and outdoor exposure tests were conducted prior to SSRT to take into account the effect of hydrogen uptake under atmospheric corrosion for the evaluation of the susceptibility of High-Strength Steels. Our studies of hydrogen embrittle properties of High-Strength Steels with 1100 to 1500 MPa of tensile Strength and a prototype ultraHigh-Strength steel with 1760 MPa containing hydrogen traps using those methods are reviewed in this article. A power law relationship between notch tensile Strength of hydrogen-precharged specimens and diffusible hydrogen content has been found. It has also been found that the local stress and the local hydrogen concentration are controlling factors of fracture. The results obtained by using SSRT after CCT and outdoor exposure test were in good agreement with the hydrogen embrittlement fracture property obtained by means of long-term exposure tests of bolts made of the High-Strength Steels.
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hydrogen entry into fe and High Strength Steels under simulated atmospheric corrosion
Electrochimica Acta, 2011Co-Authors: Eiji Akiyama, Zuogui Zhang, Tadashi Shinohara, Kaneaki TsuzakiAbstract:Abstract Electrochemical hydrogen permeation tests of Fe sheets under two cyclic corrosion test (CCT) conditions were performed to understand hydrogen entry behavior under atmospheric corrosions. Hydrogen entry into 1300 MPa-class High Strength Steels under two CCT conditions was also investigated using thermal desorption analysis. One CCT consisted of salt spray, dry and wet stages (Salt Spray CCT; SSCCT), and the other consisted of dry and wet stages after NaCl deposition (Dry–Wet CCT; DWCCT). The corrosion rates of Fe and the Steels were almost constant under SSCCT and they decreased under DWCCT with time. Nevertheless, both CCTs resulted in increases in hydrogen permeation current and diffusible hydrogen content with time indicating enhancement of hydrogen entry. Corrosion current monitored by means of an atmospheric corrosion monitoring sensor consisting of Fe anode and Ag cathode decreased obviously under dry stage of the CCTs, whereas hydrogen permeation was High at the beginning of the dry stage. The discrepancy between hydrogen entry and corrosion rate indicates that the hydrogen entry is not directly controlled by corrosion rate. Increase in acidity of underlying rust layer with growth of rust layer monitored using a W/WO 3 electrode is considered to be one of the factors affecting the hydrogen entry efficiency.
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evaluation of susceptibility of High Strength Steels to delayed fracture by using cyclic corrosion test and slow strain rate test
Corrosion Science, 2010Co-Authors: Zuogui Zhang, Songjie Li, Kaneaki Tsuzaki, Eiji Akiyama, Boping ZhangAbstract:To evaluate susceptibilities of High Strength Steels to delayed fracture, slow strain rate tests (SSRT) of notched bar specimens of AISI 4135 with tensile Strengths of 1300 and 1500 MPa and boron-bearing steel with 1300 MPa have been performed after cyclic corrosion test (CCT). During SSRT the humidity around the specimen was kept High to keep absorbed diffusible hydrogen. The fracture stresses of AISI 4135 Steels decreased with increment of diffusible hydrogen content which increased with CCT cycles. Their delayed fracture susceptibilities could be successfully evaluated in consideration of both influence of hydrogen content on mechanical property and hydrogen entry.
Andrej Atrens - One of the best experts on this subject based on the ideXlab platform.
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hydrogen trapping in some advanced High Strength Steels
Corrosion Science, 2016Co-Authors: Qinglong Liu, Jeffrey Venezuela, Mingxing Zhang, Qingjun Zhou, Andrej AtrensAbstract:Abstract Permeability experiments were used to study hydrogen diffusion and trapping in dual phase (DP), quenched and partitioned (Q&P), advanced High Strength Steels. The measured reversible hydrogen trap densities indicated that (i) trapping was less significant at a more negative potential, and (ii) the lattice diffusion coefficient of hydrogen could be measured from the partial transients at the most negative potentials. The densities of reversible hydrogen traps evaluated from complete decays from −1.700 VHg/HgO were ∼ 2 × 1018 sites cm−3, and were a factor of two Higher than those from partial decay transients between −1.700 VHg/HgO and −1.100 VHg/HgO.
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a review of hydrogen embrittlement of martensitic advanced High Strength Steels
Corrosion Reviews, 2016Co-Authors: Jeffrey Venezuela, Qinglong Liu, Mingxing Zhang, Qingjun Zhou, Andrej AtrensAbstract:The 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.
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stress corrosion cracking of High Strength Steels
Corrosion Reviews, 2013Co-Authors: Sridhar Ramamurthy, Andrej AtrensAbstract:The mechanisms of stress corrosion cracking (SCC) and hydrogen embrittlement were recently reviewed by Lynch in this journal. The present review, in contrast, focuses on the rate-limiting step of the SCC of low-alloy High-Strength Steels in water and particularly focuses on the influence of the applied stress rate on the SCC of lowalloy High-Strength Steels. Linearly increasing stress tests of low-alloy High-Strength Steels in distilled water indicated that the stress corrosion crack velocity increased with increasing applied stress rate until the maximum crack velocity, corresponding to v in fracture mechanics tests in distilled water. Moreover, the crack velocity was dependent only on the applied stress rate and was not influenced by the steel composition. The rate-limiting step could be the rupture of a surface film, which would control the rate of metal dissolution and/or the production and transport of hydrogen to the crack tip or to the regions ahead of the crack tip.
Eiji Akiyama - One of the best experts on this subject based on the ideXlab platform.
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studies of evaluation of hydrogen embrittlement property of High Strength Steels with consideration of the effect of atmospheric corrosion
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2013Co-Authors: Eiji Akiyama, Zuogui Zhang, Songjie Li, Maoqiu Wang, Yuuji Kimura, Kaneaki TsuzakiAbstract:Hydrogen embrittlement of High-Strength Steels was investigated by using slow strain rate test (SSRT) of circumferentially notched round bar specimens after hydrogen precharging. On top of that, cyclic corrosion tests (CCT) and outdoor exposure tests were conducted prior to SSRT to take into account the effect of hydrogen uptake under atmospheric corrosion for the evaluation of the susceptibility of High-Strength Steels. Our studies of hydrogen embrittle properties of High-Strength Steels with 1100 to 1500 MPa of tensile Strength and a prototype ultraHigh-Strength steel with 1760 MPa containing hydrogen traps using those methods are reviewed in this article. A power law relationship between notch tensile Strength of hydrogen-precharged specimens and diffusible hydrogen content has been found. It has also been found that the local stress and the local hydrogen concentration are controlling factors of fracture. The results obtained by using SSRT after CCT and outdoor exposure test were in good agreement with the hydrogen embrittlement fracture property obtained by means of long-term exposure tests of bolts made of the High-Strength Steels.
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hydrogen entry into fe and High Strength Steels under simulated atmospheric corrosion
Electrochimica Acta, 2011Co-Authors: Eiji Akiyama, Zuogui Zhang, Tadashi Shinohara, Kaneaki TsuzakiAbstract:Abstract Electrochemical hydrogen permeation tests of Fe sheets under two cyclic corrosion test (CCT) conditions were performed to understand hydrogen entry behavior under atmospheric corrosions. Hydrogen entry into 1300 MPa-class High Strength Steels under two CCT conditions was also investigated using thermal desorption analysis. One CCT consisted of salt spray, dry and wet stages (Salt Spray CCT; SSCCT), and the other consisted of dry and wet stages after NaCl deposition (Dry–Wet CCT; DWCCT). The corrosion rates of Fe and the Steels were almost constant under SSCCT and they decreased under DWCCT with time. Nevertheless, both CCTs resulted in increases in hydrogen permeation current and diffusible hydrogen content with time indicating enhancement of hydrogen entry. Corrosion current monitored by means of an atmospheric corrosion monitoring sensor consisting of Fe anode and Ag cathode decreased obviously under dry stage of the CCTs, whereas hydrogen permeation was High at the beginning of the dry stage. The discrepancy between hydrogen entry and corrosion rate indicates that the hydrogen entry is not directly controlled by corrosion rate. Increase in acidity of underlying rust layer with growth of rust layer monitored using a W/WO 3 electrode is considered to be one of the factors affecting the hydrogen entry efficiency.
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evaluation of susceptibility of High Strength Steels to delayed fracture by using cyclic corrosion test and slow strain rate test
Corrosion Science, 2010Co-Authors: Zuogui Zhang, Songjie Li, Kaneaki Tsuzaki, Eiji Akiyama, Boping ZhangAbstract:To evaluate susceptibilities of High Strength Steels to delayed fracture, slow strain rate tests (SSRT) of notched bar specimens of AISI 4135 with tensile Strengths of 1300 and 1500 MPa and boron-bearing steel with 1300 MPa have been performed after cyclic corrosion test (CCT). During SSRT the humidity around the specimen was kept High to keep absorbed diffusible hydrogen. The fracture stresses of AISI 4135 Steels decreased with increment of diffusible hydrogen content which increased with CCT cycles. Their delayed fracture susceptibilities could be successfully evaluated in consideration of both influence of hydrogen content on mechanical property and hydrogen entry.
Songjie Li - One of the best experts on this subject based on the ideXlab platform.
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studies of evaluation of hydrogen embrittlement property of High Strength Steels with consideration of the effect of atmospheric corrosion
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2013Co-Authors: Eiji Akiyama, Zuogui Zhang, Songjie Li, Maoqiu Wang, Yuuji Kimura, Kaneaki TsuzakiAbstract:Hydrogen embrittlement of High-Strength Steels was investigated by using slow strain rate test (SSRT) of circumferentially notched round bar specimens after hydrogen precharging. On top of that, cyclic corrosion tests (CCT) and outdoor exposure tests were conducted prior to SSRT to take into account the effect of hydrogen uptake under atmospheric corrosion for the evaluation of the susceptibility of High-Strength Steels. Our studies of hydrogen embrittle properties of High-Strength Steels with 1100 to 1500 MPa of tensile Strength and a prototype ultraHigh-Strength steel with 1760 MPa containing hydrogen traps using those methods are reviewed in this article. A power law relationship between notch tensile Strength of hydrogen-precharged specimens and diffusible hydrogen content has been found. It has also been found that the local stress and the local hydrogen concentration are controlling factors of fracture. The results obtained by using SSRT after CCT and outdoor exposure test were in good agreement with the hydrogen embrittlement fracture property obtained by means of long-term exposure tests of bolts made of the High-Strength Steels.
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evaluation of susceptibility of High Strength Steels to delayed fracture by using cyclic corrosion test and slow strain rate test
Corrosion Science, 2010Co-Authors: Zuogui Zhang, Songjie Li, Kaneaki Tsuzaki, Eiji Akiyama, Boping ZhangAbstract:To evaluate susceptibilities of High Strength Steels to delayed fracture, slow strain rate tests (SSRT) of notched bar specimens of AISI 4135 with tensile Strengths of 1300 and 1500 MPa and boron-bearing steel with 1300 MPa have been performed after cyclic corrosion test (CCT). During SSRT the humidity around the specimen was kept High to keep absorbed diffusible hydrogen. The fracture stresses of AISI 4135 Steels decreased with increment of diffusible hydrogen content which increased with CCT cycles. Their delayed fracture susceptibilities could be successfully evaluated in consideration of both influence of hydrogen content on mechanical property and hydrogen entry.
