Article
Materials Science, Multidisciplinary
K. E. Nygren, A. Nagao, S. Wang, P. Sofronis, I. M. Robertson
Summary: Internal hydrogen has a significant effect on the fatigue lifetime of SUS316L stainless steel, but a minimal impact on the tensile properties. The influence of hydrogen on the microstructural state and deformation twins results in non-linear changes in fatigue lifetime with increasing hydrogen concentration.
Article
Chemistry, Physical
Rongjian Shi, Lin Chen, Zidong Wang, Xu-Sheng Yang, Lijie Qiao, Xiaolu Pang
Summary: This study quantitatively investigated the correlation between different microstructural components and high-density hydrogen trapping in tempered niobium carbide (NbC)-precipitated martensitic steel. It was found that martensite lath and a high density of dislocations served as reversible hydrogen trapping sites, while NbC nanoprecipitates, high-angle grain boundaries, and grain-boundary precipitates acted as irreversible hydrogen traps. These findings are significant for enhancing the hydrogen embrittlement resistance of high-strength martensitic steels.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Mechanics
Luis Borja Peral, Ines Fernandez-Pariente, Chiara Colombo
Summary: This study investigates the decohesion mechanism of CrMo steel in the presence of hydrogen. Experimental tests and numerical simulations are conducted to identify the critical hydrogen concentration that induces crack tip propagation.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Rebeca Fernandez-Sousa, Covadonga Betegon, Emilio Martinez-Paneda
Summary: In this study, we investigate the influence of microstructural traps on hydrogen-assisted fatigue crack growth. A new formulation combining multi-trap stress-assisted diffusion, mechanism-based strain gradient plasticity, and a hydrogen- and fatigue-dependent cohesive zone model is presented. The results show that the ratio of loading frequency to effective diffusivity governs fatigue crack growth behavior. Increasing the density of beneficial traps, not involved in the fracture process, results in lower fatigue crack growth rates. The study identifies the combinations of loading frequency and carbide trap densities that minimize embrittlement susceptibility, providing a foundation for the rational design of hydrogen-resistant alloys.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
D. Harandizadeh Najafabadi, A. Barabi, D. Thibault, M. Brochu
Summary: In this study, the influence of hydrogen on the fatigue crack propagation rate in tempered martensitic stainless steel was investigated. An original model was proposed and validated through experiments. The results showed that there is a critical stress intensity factor range at which the impact of hydrogen on the fatigue crack propagation rate is maximum.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Mechanics
Tito Andriollo, Varvara Kouznetsova
Summary: The study reveals that the applicability of Irwin's estimate in metals with particles is questionable when the plastic zone size is comparable to the particle spacing. A new compact formula for plastic zone size is proposed in this scenario where the PZ shape differs from von Mises plasticity expectation.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Materials Science, Multidisciplinary
K. M. Bertsch, A. Nagao, B. Rankouhi, B. Kuehl, D. J. Thoma
Summary: The study examined the hydrogen embrittlement resistance of austenitic stainless steel parts manufactured using powder-bed-fed selective laser melting (SLM) and directed energy deposition (DED). The influence of hierarchical AM microstructures on mechanical response, microstructural evolution, and void formation was analyzed using multiscale electron microscopy. The presence of hydrogen affected ductility in DED materials, but had minimal impact on SLM or heat-treated materials, with microstructural features driving these different responses discussed.
Article
Engineering, Mechanical
Sang Min Lee, Sang-Youn Park, Un Bong Baek, Byoung-Ho Choi
Summary: The effect of high-pressure hydrogen on an SA-372 Grade J steel pressure vessel was analyzed through fatigue crack growth testing, fracture toughness testing, and finite element analysis. The test results, including the degradation of fracture toughness and the presence of hydrogen inflection in the fatigue crack growth rate, were used in the finite element analysis to analyze the fatigue crack growth behavior under different conditions. The residual fatigue life was evaluated considering the morphological evolution of the crack, the initial aspect ratio, and the initial crack-to-depth ratio.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Materials Science, Multidisciplinary
Ehsan Norouzi, Reza Miresmaeili, Hamid Reza Shahverdi, Mohsen Askari-Paykani, Laura Maria Vergani
Summary: The study investigated the effect of plastic deformations on the hydrogen embrittlement of TRIP steel. In situ tensile tests revealed that the total elongation loss increased by 36.8% with increasing hydrogen current density. EBSD observation showed that hydrogen charging decreased stacking fault energy, leading to the formation of more a0-martensite. The formation of a0-martensite and increased dislocation density resulted in the reversible trap sites.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Chemistry, Physical
Yuhei Ogawa, Keiichiro Iwata
Summary: This study investigates the fatigue crack growth (FCG) property of pearlitic steel in a high-pressure hydrogen gas environment. Results show that pearlitic steel exhibits less hydrogen-induced FCG acceleration compared to martensite and pure ferritic iron at the same strength level, especially under slow loading-rate conditions, which is beneficial for suppressing time-dependent cracking.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
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
Mechanics
Zahra S. Hosseini, Mohsen Dadfarnia, Akihide Nagao, Masanobu Kubota, Brian P. Somerday, Robert O. Ritchie, Petros Sofronis
Summary: Hydrogen-accelerated fatigue crack growth is a severe manifestation of hydrogen embrittlement, but a lack of a descriptive constitutive model of the hydrogen/material interaction at the macroscale hinders the development of a mechanistic and predictive model. By utilizing data from strain-controlled cyclic loading and stress-controlled ratcheting tests, a constitutive model capable of capturing material hardening or softening under cyclic straining or ratcheting can be developed.
JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
(2021)
Article
Materials Science, Multidisciplinary
Yuhei Ogawa, Keiichiro Iwata, Saburo Okazaki, Masami Nakamura, Kazuki Matsubara, Osamu Takakuwa, Hisao Matsunaga
Summary: Hydrogen affects crack-tip plastic-zone development by sharpening the crack tip shape, suppressing the extension of severely-deformed zone, and enhancing crack-tip branching, leading to a slower crack growth rate. However, it barely alters the overall plastic-zone size between in-air and hydrogen-gas conditions.
Article
Materials Science, Multidisciplinary
Guillermo Alvarez, Alfredo Zafra, Francisco Javier Belzunce, Cristina Rodriguez
Summary: This study analyzed the effect of internal hydrogen on the fatigue crack growth rate in the coarse grain region of a welded joint. It was found that internal hydrogen caused embrittlement and increased the fatigue crack growth rate, especially at low frequencies and high load ratios.
Article
Chemistry, Physical
Xiuru Fan, Zhishan Mi, Li Yang, Hang Su
Summary: In this work, first-principles methods were used to simulate the interactions between hydrogen and common alloying elements in HSLA steel. Hydrogen is being increasingly recognized as a potential clean energy source. HSLA steel, which possesses a balance of strength, toughness, and resistance to hydrogen embrittlement, is expected to be suitable for large-scale hydrogen storage and transportation. However, due to the small size of hydrogen atoms, it is challenging to directly observe the mechanism of hydrogen embrittlement through experimental methods. To understand this mechanism at the atomic level, DFT methods were applied to study the effects of alloying elements doping on the bulk and grain boundary structures of bcc-Fe. Additionally, the potential application of DFT in providing theoretical guidance for the design of HSLA steel is discussed.
Article
Materials Science, Multidisciplinary
May L. Martin, Mohsen Dadfarnia, Akihide Nagao, Shuai Wang, Petros Sofronis
Article
Chemistry, Multidisciplinary
Tao Ma, Shuai Wang, Minda Chen, Raghu Maligal-Ganesh, Lin-Lin Wang, Duane D. Johnson, Matthew J. Kramer, Wenyu Huang, Lin Zhou
Article
Materials Science, Multidisciplinary
Zhi Zeng, Jing He, Ziting Xiang, Qingqing Sun, Yongbo Wu, Shuai Wang
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2020)
Article
Materials Science, Multidisciplinary
Qingqing Sun, Yong Ni, Shuai Wang
Summary: The orientation dependence of dislocation structure in surface grain of pure copper deformed in tension was found in this study to be strongly related to grain geometry. The evolution of dislocation structure in surface grains is delayed due to the image force at the surface.
Article
Materials Science, Multidisciplinary
K. E. Nygren, A. Nagao, S. Wang, P. Sofronis, I. M. Robertson
Summary: Internal hydrogen has a significant effect on the fatigue lifetime of SUS316L stainless steel, but a minimal impact on the tensile properties. The influence of hydrogen on the microstructural state and deformation twins results in non-linear changes in fatigue lifetime with increasing hydrogen concentration.
Article
Materials Science, Multidisciplinary
Jiang Yi, Xiaoqiang Zhuang, Jing He, Minglin He, Weihong Liu, Shuai Wang
Summary: Mo-doping can improve both the strength and hydrogen resistance of CoCrNi medium-entropy alloy by promoting a twinning-dominated deformation process, which suppresses the redistribution of hydrogen concentration by dislocation motion, and thus inhibits hydrogen-induced grain boundary decohesion.
Article
Nanoscience & Nanotechnology
Jing He, Zhilin Zheng, Ziting Xiang, Huabing Li, Qingqing Sun, Shuai Wang
Summary: This study found that copper exhibits intermediate temperature embrittlement in electrical-assisted tensile tests, primarily due to the aggregation and coalescence of cavities, possibly induced by trace concentrations of sulfur solutes.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Huabing Li, Zhilin Zheng, Jing He, Akihide Nagao, Qingqing Sun, Shuai Wang
Summary: This study compared the change of dislocation structure in coarse-grained Cu in the presence and absence of hydrogen. It was found that hydrogen had minimal effect on the tensile property and dislocation evolution in coarse-grained Cu. Density functional calculation revealed that the electron structure interaction between Cu and H was the main factor inhibiting hydrogen accumulation around dislocations, thus contributing to the high resistance to hydrogen embrittlement in coarse-grained Cu.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Ziting Xiang, Qingqing Sun, Shuai Wang
Summary: We investigated the influence of discrete dislocation, dislocation cell, and cell block on the magnetic domain structure in deformed polycrystalline Ni. Our observations indicated that discrete dislocation and dislocation cell structures had a short-range effect on the local domain structure, while the dislocation cell block structure significantly changed the magnetic domain structure by generating 180 degrees domain walls. The change of magnetic property as a function of plastic deformation was discontinuous at a microscopic scale but showed a monotonic increase in coercivity and hysteresis loss at a macroscopic scale. The discrepancy between phenomena at different scales was attributed to the crystallographic orientation change during plastic deformation.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Materials Science, Multidisciplinary
Jie Yuan, Qian Liu, Shuaihang Pan, Jiaxing Li, Narayanan Murali, Shuai Wang, Xiaochun Li
Summary: In this study, TiC nanoparticles were added to high-magnesium Al-Cu-Mg alloys, which not only eliminated shrinkage porosities during casting but also significantly improved the dissolution of secondary phases. The TiC nanoparticles promoted an unusual solute dissolution behavior, breaking the thermodynamic solubility limit of magnesium in the alloy system.
Article
Chemistry, Physical
Jing He, Qian Liu, Minglin He, Jiaxing Li, Shuai Wang
Summary: This study investigated the mechanism of hydrogen embrittlement in Ni fabricated by laser-based powder bed fusion. In the presence of hydrogen, the Ni failed in a brittle mode with a transgranular-like fracture surface. This unusual fracture morphology is caused by the special grain shape induced by the laser-based manufacturing process, and the failure process is mainly attributed to intergranular decohesion. Annealing of the printed sample improved its elongation and mitigated hydrogen embrittlement. The dislocation cellular pattern formed in additive manufacturing is considered detrimental to hydrogen embrittlement resistance.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Materials Science, Multidisciplinary
Qingqing Sun, Jing He, Akihide Nagao, Yong Ni, Shuai Wang
Summary: This study systematically investigated the evolution of dislocation structures in differently orientated grains of uncharged and hydrogen-charged polycrystalline Ni. It was found that hydrogen-enhanced localized plasticity (HELP) is orientation-dependent, with the sequence [100] > [111] > [110]. The incompatibility between differently orientated grains contributes to the premature intergranular fracture of Ni, especially for the 400 ppm H-charged Ni. The relative contribution of HELP and hydrogen-enhanced decohesion (HEDE) mechanisms in hydrogen embrittlement of Ni was also analyzed quantitatively for different hydrogen concentrations.
Article
Nanoscience & Nanotechnology
Bo Du, Qian Liu, Minglin He, Jiang Yi, Jing He, Shuai Wang
Summary: In this study, the microstructure characteristics of Inconel 718 tiny pillars fabricated using laser powder bed fusion were analyzed. The results revealed a microscale heterogeneous microstructure with varying substructure sizes, arrangements of precipitates, dislocation structures, and segregation of solute atoms. The pillar center displayed a polygonal substructure without precipitates, which is different from the typical microstructure in bulk Inconel 718 alloys. Nanoindentation and micropillar compression tests showed that the transition zone had higher hardness and yield stress compared to the center and edge of the pillar. The edge and center region exhibited similar mechanical responses.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Qingqing Sun, Jing He, Jiabo Chen, Chunhong Chen, Xiaokai Guo, Fahe Cao, Shuai Wang
Summary: An Al-2Mn binary alloy with gradient microstructure and chemistry near its surface was fabricated by combining surface mechanical treatment and post-ageing treatment. The research reveals that the gradient distribution in microstructure and chemistry can significantly improve both hardness and corrosion resistance of the alloy, offering a new approach to overcome the trade-off between strength and corrosion in 3000 series Al alloys.
NPJ MATERIALS DEGRADATION
(2022)
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.
