Article
Metallurgy & Metallurgical Engineering
Filip Siska, Daria Drozdenko, Kristian Mathis, Jan Cizek, Tingting Guo, Matthew Barnett
Summary: The present study focuses on analyzing the stress and strain distribution inside and around the {10-12} twin in magnesium alloy. A 3D crystal plasticity model is used to represent the twin as an ellipsoidal inclusion surrounded by the matrix. The simulation results are consistent with experimental observations, showing a similar distribution of shear stress and activity of slip systems. Plasticity inside the twin is primarily caused by prismatic dislocation slip and does not affect twin back stress. The lateral propagation of the twin is influenced by prismatic and pyramidal slip in the twin vicinity, and the thickness of the twin is limited by the critical resolved shear stress values for dislocation slip, with basal slip playing a significant role.
JOURNAL OF MAGNESIUM AND ALLOYS
(2023)
Article
Materials Science, Multidisciplinary
Filip Siska, Ludek Stratil, Jan Cizek, Tingting Guo, Matthew Barnett
Summary: This paper investigates the interactions between {10 (1) over bar2} ten sile twin and precipitates aligned along basal planes in magnesium alloys. The results show that precipitates influence the shear stress necessary to accommodate twins, and the thickness of precipitates plays a crucial role in twin thickening and propagation.
Article
Materials Science, Multidisciplinary
Nicolo M. Della Ventura, Szilvia Kalacska, Daniele Casari, Thomas E. J. Edwards, Amit Sharma, Johann Michler, Roland Loge, Xavier Maeder
Summary: The study of extension twinning mechanism in magnesium at the micron scale revealed that basal slip triggers {10(1) over bar2} twin nucleation and favors twin growth, while pyramidal slip leads to limited {10(1) over bar2} twin growth. The critical resolved shear stress for {10(1) over bar2} twinning was found to be ten times higher than in bulk material, indicating higher ductility in the tested samples.
MATERIALS & DESIGN
(2021)
Article
Materials Science, Multidisciplinary
Mariyappan Arul Kumar, Rodney McCabe, Carlos Tome, Laurent Capolungo
Summary: This study critically analyzes the geometric compatibility factor m' for twin transmission across grain boundaries (GBs), and finds that m' cannot accurately describe and predict twin transmission events. The applicability of m' is influenced by the elastic anisotropy, plastic anisotropy, and strain levels. Local stresses play a dominant role in twin transmission compared to geometric alignment.
MATERIALS TODAY COMMUNICATIONS
(2022)
Article
Nanoscience & Nanotechnology
Yoshiki Kawano, Masatoshi Mitsuhara, Tsuyoshi Mayama, Misaki Deguchi, Zishuo Song
Summary: In this study, the criteria for {1122} compression twinning in commercially pure titanium (CP-Ti) were investigated. It was found that the dominant active twin system was {1122} compression twin, primarily activated through prismatic slip. Considering plastic deformation allowed for accurate prediction of twinning positions. The study revealed that hydrostatic pressure and resolved shear stress (RSS) may be potential criteria for {1122} twinning.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Yunwei Gui, Yujie Cui, Huakang Bian, Quanan Li, Lingxiao Ouyang, Akihiko Chiba
Summary: This study systematically investigated the microstructural evolution and deformation mechanism of an aged Mg-5Y-2Nd-3Sm-0.5Zr alloy during uniaxial compression at room temperature. The results showed a transition from slip and twinning to pyramidal II dislocations dominating the deformation mechanism.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Engineering, Mechanical
Xiaoxian Zhang, Fionn P. E. Dunne
Summary: Short crack propagation near a coherent twin boundary in polycrystal nickel alloy is investigated using 3D crystal plasticity extended finite element modelling (CP-XFEM), with experimentally characterised microstructures and crack path observations. The results show that short 3D cracks at coherent twin boundaries grow on parallel (111) slip planes at a very high rate, serving as an intrinsic part of the nucleation process. This is mainly due to the stress states established by twin/parent constraint driven by local elastic anisotropy. Elastic isotropy modelling leads to non-planar and inclined crack growth towards the twin boundary, and the twist angle between the twin and parent phase influences the local stress state, crack morphology, and growth rate deviation from 60 degrees.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Nanoscience & Nanotechnology
Kai Zhang, Zhutao Shao, Christopher S. Daniel, Mark Turski, Catalin Pruncu, Lihui Lang, Joseph Robson, Jun Jiang
Summary: The compression of a commercial cast magnesium alloy at room and cryogenic temperatures showed that cryogenic deformation resulted in higher flow stress, higher strain hardening rate, and moderately reduced strain to failure compared to room temperature deformation. This was attributed to the increased fraction of finer twins and twin twin interactions at cryogenic temperatures, which was found to be more effective in hardening than dislocation density.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Jingyu Zhang, Shiyu Du, Shurong Ding
Summary: A new system of crystal plasticity finite element models is developed in this study, considering the cooperative interactions of dislocation slip and deformation twinning. The simulation results show that optimizing the twinning activation behavior can improve the plastic deformation ability.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Engineering, Mechanical
C. Huang, B. Gao, N. Zhou, R. Xin, S. Tang, K. Elkhodary
Summary: A parameter-free grain boundary model is proposed in this paper, allowing for effective capture of twin pattern development across polycrystals. The model is applied to experimentally imaged microstructures of Magnesium and Titanium, showing a clear ability to capture the role of grain boundaries in nucleation and patterning of twins. The model demonstrates high spatiotemporal fidelity compared to electron back-scattered diffraction maps.
INTERNATIONAL JOURNAL OF PLASTICITY
(2022)
Article
Materials Science, Multidisciplinary
Yingjun Sun, Kecheng Zhou, Hua Qiao, Renlong Xin, Huamiao Wang, Peidong Wu
Summary: For polycrystalline materials with the deformation mechanism of twinning, the interaction between the twins and grain boundaries play a significant role in their deformation behavior. In this study, the twin transmission across grain boundaries in a magnesium bicrystal was investigated using a crystal plasticity finite element model, with factors like crystallographic orientation, GB misorientation, CRSS, dislocation slip, and twin-induced stress relaxation considered. The CSF was found to interpret twin transmission better and accurately capture the fraction of twin-transmitted grain boundaries.
MATERIALS TODAY COMMUNICATIONS
(2022)
Article
Metallurgy & Metallurgical Engineering
Krishna Yaddanapudi, Mariyappan Arul Kumar, Jiaxiang Wang, Xin Wang, Timothy J. Rupert, Enrique J. Lavernia, Julie M. Schoenung, Irene J. Beyerlein, Subhash Mahajan
Summary: This study investigates the effects of twin-twin interactions on the distribution of defects and stress fields in a magnesium alloy. The analysis focuses on a specific twin junction in a deformed Mg-3wt.%Y alloy. The results show that the morphology of the twins is asymmetric and the dislocations concentrate near the twin-twin junction site. Crystal plasticity calculations suggest that the local stress fields generated at the junction site are responsible for the observed concentration of dislocations. These findings provide insights into the twinning behavior and mechanical properties of Mg alloys.
JOURNAL OF MAGNESIUM AND ALLOYS
(2023)
Article
Materials Science, Multidisciplinary
Duncan W. MacLachlan, Vasilis Karamitros, Fionn P. E. Dunne
Summary: This paper proposes an engineering approach to the problem of fatigue crack initiation at the microstructural scale. The initiation of fatigue cracks is broken down into separate processes, and a fundamental approach to modelling these processes has been developed. The method successfully correlates with fatigue data for a specific material.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Metallurgy & Metallurgical Engineering
Xin Wang, Dikai Guan
Summary: The nucleation and grain growth of 34 coarse grains were tracked using a quasi-in-situ EBSD method. Most grains did not have a basal orientation, and no preferential grain growth or special types of grain boundaries were observed. Nine coarse grains nucleated from deformed grain boundaries, mainly within dislocation cells or subgrains in deformed grain interiors. The growth behavior of these grains can be explained by abnormal subgrain growth rarely reported in Mg alloys. The coarse basal grains did not show any growth advantage compared to other non-basal grains, resulting in a weak basal texture in the AZ31B alloy.
JOURNAL OF MAGNESIUM AND ALLOYS
(2022)
Article
Nanoscience & Nanotechnology
Pengbin Lu, Lifei Wang, Liangliang Xue, Guangsheng Huang, Liuwei Zheng, Hongxia Wang, Kwang Seon Shin
Summary: The ductility of pure magnesium was enhanced about 3 times at room temperature compared with the initial material due to the proposed concept of shear strain-induced twin orientation regulation (SITOR), where shear deformation was introduced to regulate the initial tension twin orientation, resulting in a larger Schmid factor of basal slip, thus improving the plasticity of pure Mg significantly.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Metallurgy & Metallurgical Engineering
Jun Cheng, Tingting Guo, Matthew R. Barnett
Summary: This paper examines the temperature sensitivity of tensile twinning in a magnesium single crystal during nanoindentation. It is found that the generation of twinning is temperature-dependent, with a decrease in pop-in load as temperature increases. The activation energy obtained from thermal activation analysis is consistent with the observations.
JOURNAL OF MAGNESIUM AND ALLOYS
(2022)
Article
Materials Science, Multidisciplinary
Claudius Dichtl, David Lunt, Michael Atkinson, Rhys Thomas, Adam Plowman, Bartosz Barzdajn, Rebecca Sandala, Joao Quinta da Fonseca, Michael Preuss
Summary: This study investigated two different bimodal microstructures of near-alpha titanium alloys to shed light on the deformation mechanisms during cold dwell. It was found that basal slip is initially dominant at low stress levels, while prismatic slip increases approaching the yield stress. Additionally, the sample with coarse transformation product exhibited more plastic strain and longer slip traces, indicating higher susceptibility to cold creep deformation.
Article
Nanoscience & Nanotechnology
J. Joseph, M. Annasamy, S. R. Kada, P. D. Hodgson, M. R. Barnett, D. M. Fabijanic
Summary: This study analyzed the effect of the relative contents of Al and Ti on the equilibrium phase formation in a novel high entropy superalloy system. Lower Al/Ti ratio improved the mechanical properties of the alloy.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Hossein Beladi, Ehsan Farabi, Peter D. Hodgson, Matthew R. Barnett, Gregory S. Rohrer, Daniel Fabijanic
Summary: Solid-state additive friction stir deposition was used for three-dimensional printing of 316L stainless steel. The resulting microstructure was exceptionally fine, with a significantly different misorientation angle distribution from the original material, and a texture showing strong shear components.
PHILOSOPHICAL MAGAZINE
(2022)
Article
Nanoscience & Nanotechnology
Jun Wang, Mahmoud Reza Ghandehari Ferdowsi, Peter A. Lynch, Sitarama R. Kada, Matthew R. Barnett
Summary: This study investigates the effects of age hardening on different types of twinning in magnesium alloys, specifically in alloy Mg-6.5Zn with bimodal textures. It was found that tensile twinning is stimulated by precipitates while compression twinning is suppressed by them. This difference is attributed to lower twin surface energy and a larger twinning dislocation Burgers vector in compression twins.
SCRIPTA MATERIALIA
(2022)
Article
Mechanics
Alban de Vaucorbeil, Vinh Phu Nguyen, Christopher R. Hutchinson, Matthew R. Barnett
Summary: This paper presents a study on the Total Lagrangian Material Point Method (TLMPM) for simulating scratch tests, showing its stability and accuracy through comparisons with experimental results and existing research.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2022)
Article
Nanoscience & Nanotechnology
Jun Wang, Mahmoud Reza Ghandehari Ferdowsi, Sitarama Raju Kada, Steven Babaniaris, Bevis Hutchinson, Peter A. Lynch, Matthew R. Barnett
Summary: The C-texture appears in Mg-6.5Zn alloy with heavy alloying and higher extrusion ratios. It is not solely linked to the presence of second phase particles, and the starting texture is not essential for its formation. The promoted pyramidal < c + a > slip mechanism is likely responsible for its formation.
SCRIPTA MATERIALIA
(2022)
Article
Engineering, Multidisciplinary
J. D. Robson
Summary: This study implemented a simple finite element Mott model to investigate the fragmentation effect of a thin walled ring, and explored the influence of local variations in fracture strain around the ring. The results showed that the characteristic Mott distribution of fragment size can be reproduced successfully, regardless of the random distribution of fracture strains or the choice of function used to describe the fracture strain scatter, as long as a sufficient number of simulations are run.
DEFENCE TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Berzah Yavuzyegit, Egemen Avcu, Albert D. Smith, Jack M. Donoghue, David Lunt, Joseph D. Robson, Timothy L. Burnett, Joao Quinta da Fonseca, Philip J. Withers
Summary: By coupling an improved speckle patterning method enabling high resolution digital image correlation (HRDIC) at nanoscale strain resolution with a scanning electron microscope allowing autonomous experimental control and image acquisition during in situ tensile straining, the plastic deformation in AZ31 Mg alloy at the grain scale to significant plastic strains has been mapped for the first time. The proposed methodologies have the potential to characterise the real-time deformation behaviour of a wide range of engineering alloys at the grain scale at room and elevated temperatures.
Article
Nanoscience & Nanotechnology
J. D. Robson, M. J. Lawson, J. M. Donoghue, J. Guo, A. E. Davis
Summary: Discontinuous precipitation (DP) is a common mechanism for solid solution decomposition, resulting in the formation of precipitate layers and solute depleted matrix along a moving boundary. The morphology of DP regions is highly complex, and the behavior of dislocations and twins within such structures during deformation is not well understood. A 3-dimensional (3D) analysis is necessary to reveal the true morphology of DP. This study presents the first 3D investigation of DP using a novel PFIB based serial sectioning method. The AZ80 alloy studied exhibits an interconnected network of DP regions within a connected matrix, with varying widths of DP regions.
SCRIPTA MATERIALIA
(2023)
Article
Materials Science, Multidisciplinary
Yi Yang, Veronique Massardier, Mahmoud Reza Ghandehari Ferdowsi, Lu Jiang, Jun Wang, Thomas Dorin, Sitarama R. Kada, Matthew R. Barnett, Michel Perez
Summary: This study provides new insights into the precipitation kinetics in Mg-Zn alloys. Through the characterization of the evolution of Zn solute, precipitate size, and volume fraction using various techniques, the experimental results are supported by a precipitation model based on classical nucleation and growth theories. The study reveals the prevalence of rod-shaped precipitates in the early aging stage and plate-shaped precipitates in the overaging stage.
Article
Materials Science, Multidisciplinary
D. Lunt, R. Thomas, D. Bowden, M. T. P. Rigby-Bell, S. de Morae Shubeita, C. Andrews, T. Lapauw, J. Vleugels, J. Quinta da Fonseca, K. Lambrinou, P. Frankel
Summary: This work proposes a novel approach to detect strain localisation caused by irradiation-induced damage in nuclear materials on the microstructural level. High-resolution digital image correlation (HRDIC) is used to determine local strains and generate high-resolution strain maps, which can help understand the effects of irradiation-induced dimensional change and cracking. The combination of scanning electron microscopy (SEM) and HRDIC is demonstrated to measure irradiation-induced dimensional changes in three different materials and is crucial in designing microstructures that are structurally resilient during irradiation.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Charline Le Nue, Santiago Corujeira Gallo, Alireza Vahid, Jiangting Wang, Mehdi Taherishargh, Hooyar Attar, Daniel Fabijanic, Matthew Barnett
Summary: High-chromium cast irons are commonly used for wear-resistant applications, and there is ongoing debate on the secondary carbide types during heat treatment. This study examines the microstructural evolution of a hypoeutectic high-chromium cast iron and finds that M23C6 secondary carbides precipitate during heating, while higher temperatures result in the formation of both M23C6 and M7C3 secondary carbides. The carbon content of the matrix plays a significant role in determining the martensite start temperature and bulk hardness.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
R. Thomas, D. Lunt, M. D. Atkinson, J. Quinta da Fonseca, M. Preuss, P. Honniball, P. Frankel
Summary: This study quantifies the strain partitioning between different phases in zirconium alloys using high-resolution digital image correlation and electron backscatter diffraction. It was found that the average strain in hydrides and precipitates was lower than in the α-Zr matrix after tensile deformation. Shear bands in the α-Zr matrix interacted with hydrides in various ways, while large hydrides had a particularly detrimental effect on deformation behavior. The Zr(Fe,Cr)2 precipitates remained undeformed and forced the expected lattice rotation in the metal matrix.
Article
Engineering, Manufacturing
Ehsan Farabi, Steven Babaniaris, Matthew R. Barnett, Daniel M. Fabijanic
Summary: The additive friction stir deposition (AFSD) of Ti6Al4V alloy was performed successfully with improved ductility and strength of the deposited state, achieved by the reduction of deposition temperature and refinement of the as-deposited phase structure.
ADDITIVE MANUFACTURING LETTERS
(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.
