Article
Engineering, Mechanical
Chengshuang Zhou, Bei Fang, Jing Wang, Dan Tang, Huimin Tao, Yanming He, Zhengrong Zhou, Changfeng Chen, Lin Zhang
Summary: The behavior of as-received and cold-rolled Fe-25Mn-10Ni-0.65C twinning-induced plasticity steel in hydrogen environment was studied using fatigue crack growth rate tests. It was found that TWIP steel exhibits weak hydrogen embrittlement susceptibility due to the formation of deformation twins at the crack tip. Cold rolling was shown to significantly improve the hydrogen embrittlement resistance and fatigue resistance of TWIP steel.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Nanoscience & Nanotechnology
Chengshuang Zhou, Dan Tang, Kaiyu Zhang, Fangyue Wu, Ping Lin, Yan Jin, Lin Zhang, Jinyang Zheng
Summary: The hydrogen embrittlement behavior of two stabilized austenitic TWIP steels under high-pressure thermal hydrogen charging and hydrogen environment were investigated. It was found that both TWIP steels showed a certain susceptibility to hydrogen embrittlement after hydrogen charging, with the TWIP steel with higher Mn content showing weaker hydrogen embrittlement.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Nanoscience & Nanotechnology
Cheng Zhang, Huihui Zhi, Stoichko Antonov, Jun He, Hang Yu, Zihui Guo, Yanjing Su
Summary: The effect of deformation twins on the hydrogen embrittlement of TWIP steel was investigated, and the results showed that specimens with high twin volume fraction exhibited better resistance to hydrogen embrittlement.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Nanoscience & Nanotechnology
Dong Wang, Xu Lu, Di Wan, Xiaofei Guo, Roy Johnsen
Summary: The hydrogen embrittlement behavior of Fe-22Mn-0.6C TWIP steel was studied using in-situ SEM observation, EBSD, and ECCI techniques. Hydrogen pre-charging decreased mechanical properties and caused a ductile-to-brittle fracture transition. The threshold hydrogen content for this transition was determined using TDS analysis and hydrogen diffusion calculation. LAGBs showed better resistance to crack initiation and propagation compared to HAGBs, with stress concentration and hydrogen effects at grain boundaries intersecting with deformation twins identified as reasons for crack initiation and propagation.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Metallurgy & Metallurgical Engineering
Abbas Mohammadi, Motomichi Koyama, Gregory Gerstein, Hans Jurgen Maier, Hiroshi Noguchi
Summary: The study investigated hydrogen-assisted crack growth in pre-strained TWIP steel, using artificial defects as crack initiation sites. Quasi-cleavage crack propagation was observed due to repeated crack initiation near the crack tip and subsequent coalescence. The early stage of plasticity-driven crack growth was sensitive to the crack length and remote stress level.
ISIJ INTERNATIONAL
(2021)
Article
Nanoscience & Nanotechnology
L. Claeys, T. Depover, K. Verbeken
Summary: The hydrogen embrittlement sensitivity of three twinning-induced plasticity steels was investigated. The addition of aluminium and increased manganese content were found to affect the hydrogen solubility and diffusivity, as well as the mechanical properties of the steels. Aluminium addition led to increased resistance to hydrogen, while manganese addition reduced the resistance, despite having the same stacking fault energy. The critical hydrogen concentration may be higher with the addition of aluminium.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Nanoscience & Nanotechnology
Cheng Zhang, Huihui Zhi, Stoichko Antonov, Lin Chen, Yanjing Su
Summary: The presence of hydrogen was found to decrease twin thickness and increase twin density in TWIP austenitic steel, influencing its hydrogen embrittlement behavior. This phenomenon, termed hydrogen-enhanced densified twinning, plays an important role in the twinning process of TWIP austenitic steel.
SCRIPTA MATERIALIA
(2021)
Article
Materials Science, Multidisciplinary
Futao Dong, Jeffrey Venezuela, Huixing Li, Zhiming Shi, Qingjun Zhou, Liansheng Chen, Jun Chen, Linxiu Du, Andrej Atrens
Summary: The effect of Cu alloying on hydrogen embrittlement (HE) in TWIP steel was investigated. Cu alloying influenced HE resistance through several mechanisms including the increase in stacking fault energy, refinement of austenite grains, reduction of diffusible hydrogen content, and dispersion of mechanical twins by Cu precipitate/Cu-rich clusters. Among these mechanisms, (iv) exhibited the greatest improvement in HE resistance in the 700°C annealed Cu-alloyed TWIP steel.
Article
Nanoscience & Nanotechnology
Akinobu Shibata, Ivan Gutierrez-Urrutia, Kazuho Okada, Goro Miyamoto, Yazid Madi, Jacques Besson, Kaneaki Tsuzaki
Summary: The study investigated the relationship between the mechanical response and microscopic crack propagation behavior of hydrogen-related intergranular fractures in high-strength martensitic steel. The results showed that hydrogen can affect crack tip morphology and induce strain localization in the vicinity of intergranular cracks.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Xiaofei Guo, Stefan Zaefferer, Fady Archie, Wolfgang Bleck
Summary: The addition of hydrogen significantly affects the mechanical properties and fracture behavior of Fe-22Mn-0.6C twinning induced plasticity steel, leading to high susceptibility to hydrogen embrittlement and promoting the development of planar dislocation structures, twinning, and micro-voids at grain boundaries.
INTERNATIONAL JOURNAL OF MINERALS METALLURGY AND MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Hao Fu, Wenhao He, Zhishan Mi, Yu Yan, Jianliang Zhang, Jinxu Li
Summary: In this study, the heterogeneous plastic strain in twinning-induced plasticity (TWIP) steel after hydrogen charging was quantitatively characterized, and the deformation mode and initiation mechanism of hydrogen-induced crack (HIC) were clarified. Statistical analysis demonstrated that the cracked grain boundary and its vicinity exhibited high strain incompatibility, which was found to be the key factor for HIC initiation.
Article
Chemistry, Physical
Milene Yumi Maeda, Motomichi Koyama, Hayato Nishimura, Osvaldo Mitsuyuki Cintho, Eiji Akiyama
Summary: Hydrogen has significant effects on the ductility loss and fracture behavior of nitrogen-doped duplex stainless steel, resulting in quasi-cleavage and intergranular fractures associated with transgranular austenite cracking and ferrite/austenite interface cracking, respectively. Deformation twinning in austenite and nitrogen-related solution hardening are crucial factors leading to brittle-like cracking.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Nanoscience & Nanotechnology
C. D'Hondt, V Doquet, J. P. Couzinie
Summary: In situ tensile and reversed cyclic tests were conducted on a TWIP steel in a SEM, showing evidence of twinning/detwinning processes and their effects. It was observed that detwinning and retwinning occurred partially after load reversal, with stress variations close to twinning stress affecting the mechanical hysteresis of the material.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Mechanics
Zhuang Chen, Diansen Yang, Hanbing Bian
Summary: This paper presents a peridynamic hydrogen embrittlement model that is capable of simulating hydrogen diffusion and hydrogen embrittlement phenomena. The effectiveness of the model is validated through numerical examples and compared to other models and experiments. The influence of hydrogen diffusion time steps and grain boundary diffusion coefficients on hydrogen-assisted crack propagation is also investigated.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Nanoscience & Nanotechnology
Zen-Hao Lai, Yi-Ting Lin, Yi-Hsuan Sun, Jui-Fan Tu, Hung-Wei Yen
Summary: This study identified a hydrogen-induced ductilization phenomenon in a specific austenitic lightweight TWIP steel, which is influenced by hydrogen and deformation twinning during deformation, preventing hydrogen embrittlement.
SCRIPTA MATERIALIA
(2022)
Article
Nanoscience & Nanotechnology
Motomichi Koyama, Shunsuke Mizumachi, Eiji Akiyama, Kaneaki Tsuzaki
Summary: The effect of hydrogen on the resistance to mechanically long fatigue crack growth in an equiatomic Fe-Cr-Ni-Mn-Co high-entropy alloy was investigated. Hydrogen charging resulted in accelerated intergranular crack growth via a plasticity-driven mechanism.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Atsushi Omori, Saya Ajito, Hiroshi Abe, Kuniki Hata, Tomonori Sato, Yoshiyuki Kaji, Hiroyuki Inoue, Mitsumasa Taguchi, Hajime Seito, Eiji Tada, Shunichi Suzuki, Eiji Akiyama
Summary: The effect of oxidants, such as ozone, formed by the radiolysis of water on the corrosion of carbon steel in a humid environment was evaluated. The study found that ozone accelerated the corrosion of carbon steel, with corrosion rates increasing with relative humidity and ozone concentration.
MATERIALS TRANSACTIONS
(2022)
Article
Engineering, Mechanical
Atsuki Setoyama, Yuhei Ogawa, Masami Nakamura, Yuya Tanaka, Tingshu Chen, Motomichi Koyama, Hisao Matsunaga
Summary: Increased strength levels result in accelerated fatigue crack growth caused by hydrogen. In the highest-strength material, the crack growth rate per cycle depends on the test frequency, proportional to load duration. The hydrogen-induced fatigue crack growth is due to stress-driven cracking along hierarchical martensite boundaries, caused by the degradation of interface strength as a result of competition between driving stress and resistance stress.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Chemistry, Physical
Hiroshi Kakinuma, Saya Ajito, Tomohiko Hojo, Motomichi Koyama, Sachiko Hiromoto, Eiji Akiyama
Summary: In this study, the distribution of hydrogen entering an Fe sheet under a droplet of NaCl solution was successfully visualized using a hydrogenochromic sensor. The entry of hydrogen was initially difficult to confirm, but became observable as the corrosion progressed, with the preferential entry site corresponding to the rust-formed area. The study postulates that the decrease in pH due to hydrolysis reactions of Fe ions under the rust promotes the entry of hydrogen.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Materials Science, Multidisciplinary
Yutao Zhou, Motomichi Koyama, Tomohiko Hojo, Saya Ajito, Eiji Akiyama
Summary: In this study, the temperature dependence of microstructure and damage evolution in medium Mn steel was investigated. The results showed that deformation temperatures had a significant impact on the flow behavior, work hardening rate, and mechanical properties of the steel. Deformation-induced martensite acted as the initiation site of damage, and the critical strain and probability of damage initiation decreased with decreasing deformation temperature. Furthermore, the decrease in temperature deteriorated the micro-damage arrestability of ferrite, resulting in a transition from ductile to quasi-cleavage fractures.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2023)
Article
Chemistry, Physical
Rama Srinivas Varanasi, Motomichi Koyama, Hiroyuki Saitoh, Reina Utsumi, Toyoto Sato, Shin-ichi Orimo, Eiji Akiyama
Summary: The phase transformations and microstructure changes during the depressurization of non-hydrogenated and hydrogenated Fe-Mn-Si-Cr alloy were investigated. Understanding the effects of hydrogenation on the stability of the austenite phase in Fe-based alloys is crucial.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Nanoscience & Nanotechnology
Yota Masuda, Motomichi Koyama, Hiroshi Kakinuma, Eiji Akiyama
Summary: The effects of mechanical loading on hydrogen uptake were studied using thermal desorption experiments. The diffusible hydrogen content increased with increasing elastic and plastic strains, with a larger increase per elastic strain than per plastic strain.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Hao Luo, Van Hoang Nguyen, Kazuhiro Gotoh, Saya Ajito, Tomohiko Hojo, Yasuyoshi Kurokawa, Eiji Akiyama, Noritaka Usami
Summary: This study investigates the effect of post-oxidizing treatment (POT) on the structural, optical, and passivation performances of titanium oxide coated crystalline Si (c-Si) heterostructures prepared by the solution process. The results show that POT improves the passivation performance by oxidizing the TiOx film, c-Si surface, and forming POx.
Article
Materials Science, Multidisciplinary
Saya Ajito, Tomohiko Hojo, Motomichi Koyama, Sachiko Hiromoto, Eiji Akiyama
Summary: The environment-assisted cracking behavior of AZ31 magnesium alloy was studied through tensile tests in a Na2B4O7·10H2O solution containing NH4SCN and in air at cathodic and corrosion potentials. Mechanical properties of AZ31 were unaffected by the environment at an initial strain rate of 10-4s-1, but degraded in the solution at an initial strain rate of 10-6s-1. Higher potentials resulted in smaller total elongation, while positive potential shift increased the average hydrogen absorption rate. These findings indicate that environment-assisted cracking becomes more severe under relatively high potential due to corrosion and enhanced hydrogen absorption.
Article
Nanoscience & Nanotechnology
Yutao Zhou, Tomohiko Hojo, Motomichi Koyama, Saya Ajito, Eiji Akiyama
Summary: Hydrogen and deformation temperature have significant effects on micro-damage evolution and fracture behavior of TRIP-aided steel. Hydrogen uptake increases micro-damage density and changes fracture mode at different deformation temperatures.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Nanoscience & Nanotechnology
Tingshu Chen, Motomichi Koyama, Takahiro Chiba, Eiji Akiyama, Kenichi Takai
Summary: The effects of the misorientation of prior austenite grain boundary (PAGB) segments on the local plasticity evolution in intergranular (IG) and IG-like fractures were investigated. The study found that low-angle and sigma 3 PAGB segments allow crack-tip blunting before crack growth.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Y. Liu, K. Zweiacker, C. Liu, J. T. McKeown, J. M. K. Wiezorek
Summary: The evolution of rapid solidification microstructure and solidification interface velocity of hypereutectic Al-20at.%Cu alloy after laser melting has been studied experimentally. It was found that the formation of microstructure was dominated by eutectic, alpha-cell, and banded morphology grains, and the growth modes changed with increasing interface velocity.
Article
Materials Science, Multidisciplinary
Bharat Gwalani, Julian Escobar, Miao Song, Jonova Thomas, Joshua Silverstein, Andrew Chihpin Chuang, Dileep Singh, Michael P. Brady, Yukinori Yamamoto, Thomas R. Watkins, Arun Devaraj
Summary: Castable alumina forming austenitic alloys exhibit superior creep life and oxidation resistance at high temperatures. This study reveals the mechanism behind the enhanced creep performance of these alloys by suppressing primary carbide formation and offers a promising alloy design strategy for high-temperature applications.
Article
Materials Science, Multidisciplinary
Jian Song, Qi Zhang, Songsong Yao, Kunming Yang, Houyu Ma, Jiamiao Ni, Boan Zhong, Yue Liu, Jian Wang, Tongxiang Fan
Summary: Recent studies have shown that achieving an atomically flat surface for metals can greatly improve their oxidation resistance and enhance their electronic-optical applications. Researchers have explored the use of graphene as a covering layer to achieve atomically flat surfaces. They found that high-temperature deposited graphene on copper surfaces formed mono-atomic steps, while annealed copper and transferred graphene on copper interfaces formed multi-atomic steps.
Article
Materials Science, Multidisciplinary
Jennifer A. Glerum, Jon-Erik Mogonye, David C. Dunand
Summary: Elemental powders of Al, Ti, Sc, and Zr are blended and processed via laser powder-bed fusion to create binary and ternary alloys. The microstructural analysis and mechanical testing show that the addition of Ti results in the formation of primary precipitates, while the addition of Sc and Zr leads to the formation of fine grain bands. The Al-0.25Ti-0.25Zr alloy exhibits comparable strain rates to Al-0.5Zr at low stresses, but significantly higher strain rates at higher stresses during compressive creep testing. Finite element modeling suggests that the connectivity of coarse and fine grain regions is a critical factor affecting the creep resistance of the alloys.
Article
Materials Science, Multidisciplinary
P. Jannotti, B. C. Hornbuckle, J. T. Lloyd, N. Lorenzo, M. Aniska, T. L. Luckenbaugh, A. J. Roberts, A. Giri, K. A. Darling
Summary: This work characterizes the thermo-mechanical behavior of bulk nanocrystalline Cu-Ta alloys under extreme conditions. The experiments reveal that the alloys exhibit unique mechanical properties, behaving differently from conventional nanocrystalline Cu. They do not undergo grain coarsening during extrusion and exhibit behavior similar to coarse-grained Cu.
Article
Materials Science, Multidisciplinary
Yiqing Wei, Jingwei Li, Daliang Zhang, Bin Zhang, Zizhen Zhou, Guang Han, Guoyu Wang, Carmelo Prestipino, Pierric Lemoine, Emmanuel Guilmeau, Xu Lu, Xiaoyuan Zhou
Summary: This study proposes a new strategy to modify microstructure by phase regulation, which can simultaneously enhance carrier mobility and reduce lattice thermal conductivity. The addition of Cu in layered SnSe2 induces a phase transition that leads to increased grain size and reduced stacking fault density, resulting in improved carrier mobility and lower lattice thermal conductivity.
Article
Materials Science, Multidisciplinary
Jia Chen, Zhengyu Zhang, Eitan Hershkovitz, Jonathan Poplawsky, Raja Shekar Bhupal Dandu, Chang-Yu Hung, Wenbo Wang, Yi Yao, Lin Li, Hongliang Xin, Honggyu Kim, Wenjun Cai
Summary: In this study, the structural origin of the pH-dependent repassivation mechanisms in multi-principal element alloys (MPEA) was investigated using surface characterization and computational simulations. It was found that selective oxidation in acidic to neutral solutions leads to enhanced nickel enrichment on the surface, resulting in reduced repassivation capability and corrosion resistance.
Article
Materials Science, Multidisciplinary
X. Y. Xu, C. P. Huang, H. Y. Wang, Y. Z. Li, M. X. Huang
Summary: The limited slip systems of magnesium (Mg) and its alloys hinder their wide applications. By conducting tensile straining experiments, researchers discovered a rate-dependent transition in the dislocation mechanisms of Mg alloys. At high strain rates, glissile dislocations dominate, while easy-glide dislocations dominate at low strain rates. Abundant glissile dislocations do not necessarily improve ductility.
Article
Materials Science, Multidisciplinary
M. S. Szczerba, M. J. Szczerba
Summary: Inverse temperature dependences of the detwinning stress were observed in face-centered cubic deformation twins in Cu-8at.%Al alloy. The detwinning stress increased with temperature when the pi detwinning mode was involved, but decreased when the pi/3 mode was involved. The dual effect of temperature on the detwinning stress was due to the reduction of internal stresses pre-existing within the deformation twins. The complete reduction of internal stresses at about 530 degrees C led to the equivalence of the critical stresses of different detwinning modes and a decrease in the yield stress anisotropy of the twin/matrix structure.
Article
Materials Science, Multidisciplinary
Taowen Dong, Tingting Qin, Wei Zhang, Yaowen Zhang, Zhuoran Feng, Yuxiang Gao, Zhongyu Pan, Zixiang Xia, Yan Wang, Chunming Yang, Peng Wang, Weitao Zheng
Summary: The interaction between the electrode and the electric double layer (EDL) significantly influences the energy storage mechanism. By studying the popular alpha-Fe2O3 electrode and the EDL interaction, we find that the energy storage mechanism of the electrode can be controlled by modulating the EDL.
Article
Materials Science, Multidisciplinary
Matthew R. Barnett, Jun Wang, Sitarama R. Kada, Alban de Vaucorbeil, Andrew Stevenson, Marc Fivel, Peter A. Lynch
Summary: The elastic-plastic transition in magnesium alloy Mg-4.5Zn exhibits bursts of deformation, which are characterized by sudden changes in grain orientation. These bursts occur in a coordinated manner among nearby grains, with the highest burst rate observed at the onset of full plasticity. The most significant burst events are associated with twinning, supported by the observation of twinned structures using electron microscopy. The bursts are often preceded and followed by a stasis in peak movement, indicating a certain "birth size" for twins upon formation and subsequent growth at a later stage.
Article
Materials Science, Multidisciplinary
Vaidehi Menon, Sambit Das, Vikram Gavini, Liang Qi
Summary: Understanding solute segregation thermodynamics is crucial for investigating grain boundary properties. The spectral approach and thermodynamic integration methods can be used to predict solute segregation behavior at grain boundaries and compare with experimental observations, thus aiding in alloy design and performance control.
Article
Materials Science, Multidisciplinary
Feiyu Qin, Lei Hu, Yingcai Zhu, Yuki Sakai, Shogo Kawaguchi, Akihiko Machida, Tetsu Watanuki, Yue-Wen Fang, Jun Sun, Xiangdong Ding, Masaki Azuma
Summary: This study reports on the negative and zero thermal expansion properties of Cd2Re2O7 and Cd1.95Ni0.05Re2O7 materials, along with their ultra-low thermal conductivity. Through investigations of their structures and phonon calculations, the synergistic effect of local structure distortion and soft phonons is revealed as the key to achieving these distinctive properties.
Article
Materials Science, Multidisciplinary
Thomas Beerli, Christian C. Roth, Dirk Mohr
Summary: A novel testing system for miniature specimens is designed to characterize the plastic response of materials for which conventional full-size specimens cannot be extracted. The system has an automated operation process, which reduces the damage to specimens caused by manual handling and improves the stability of the test results. The experiments show that the miniature specimens extracted from stainless steel and aluminum have high reproducibility, and the results are consistent with those of conventional-sized specimens. A correction procedure is provided to consider the influence of surface roughness and heat-affected zone caused by wire EDM.
Article
Materials Science, Multidisciplinary
Rani Mary Joy, Paulius Pobedinskas, Nina Baule, Shengyuan Bai, Daen Jannis, Nicolas Gauquelin, Marie-Amandine Pinault-Thaury, Francois Jomard, Kamatchi Jothiramalingam Sankaran, Rozita Rouzbahani, Fernando Lloret, Derese Desta, Jan D'Haen, Johan Verbeeck, Michael Frank Becker, Ken Haenen
Summary: This study investigates the influence of film microstructure and composition on the Young's modulus and residual stress in nanocrystalline diamond thin films. The results provide insights into the mechanical properties and intrinsic stress sources of these films, and demonstrate the potential for producing high-quality nanocrystalline diamond films under certain conditions.
