Article
Materials Science, Multidisciplinary
Alec I. Saville, Amy J. Clarke
Summary: This study introduces a reconstruction process to evaluate the microstructural evolution of the high temperature fl-Ti phase in a Ti-Cu binary alloy. While the reconstruction of martensitic microstructures was successful, the reconstruction of pearlitic microstructures was not effective. However, this analysis provided new insights into the interfacial crystallographic orientations of pearlitic Ti-Cu microstructures.
MATERIALS CHARACTERIZATION
(2023)
Article
Metallurgy & Metallurgical Engineering
Shigekazu Morito, Anh Hoang Pham, Taisuke Hayashi, Goro Miyamoto, Tadashi Furuhara
Summary: The toughness of martensitic steels is strongly related to their fine and complex morphologies. The effect of carbon content on the morphology of lath martensite must be studied. The block structure in low-carbon martensite is more entangled with each other than that of ultra-low-carbon martensite.
ISIJ INTERNATIONAL
(2022)
Article
Materials Science, Multidisciplinary
Gavin Hennessey, Travis Peters, Pannawit Tipsawat, Marti Checa, Liam Collins, Susan Trolier-McKinstry
Summary: This paper investigates the effect of microstructural features on domain wall motion pinning in PZT films on polycrystalline substrates. The study reveals that the behavior varies with the misorientation angle and proximity to grain boundaries. Random grain boundaries exhibit deeper minima and larger widths of influence compared to coincident site lattice boundaries. Triple points with more random boundaries exhibit non-Rayleigh behavior, suggesting deep potential minima or regions unfavorable for domain wall motion.
Article
Multidisciplinary Sciences
J. C. Stinville, J. M. Hestroffer, M. A. Charpagne, A. T. Polonsky, M. P. Echlin, C. J. Torbet, V. Valle, K. E. Nygren, M. P. Miller, O. Klaas, A. Loghin, I. J. Beyerlein, T. M. Pollock
Summary: The development of high-fidelity mechanical property prediction models relies on large volumes of microstructural feature data. However, spatially correlated measurements of 3D microstructure and deformation fields have been rare. This study presents a unique multi-modal dataset that combines state-of-the-art experimental techniques for 3D tomography and high-resolution deformation field measurements.
Article
Materials Science, Multidisciplinary
Chunfeng Du, Yipeng Gao, Yizhen Li, Min Zha, Peng Chen, Yunhe Sheng, Heng-Nan Liang, Hui-Yuan Wang
Summary: Crystalline defects such as dislocations, disclinations, and grain boundaries play a crucial role in determining the mechanical and functional properties of metallic materials. This study proposes a Lie-algebra-based method to quantify the rotational properties of disclinations and introduces a convenient way to determine disclination density distribution from Electron Backscatter Diffraction data. Through quasiin-situ Electron Backscatter Diffraction characterizations, three major formation mechanisms of disclinations have been identified in deformed polycrystalline Mg alloys, which can be treated as topological reactions among various types of defects. This work not only suggests a new mathematical tool to investigate the interactions and reactions among multiple types of crystalline defects but also provides a new insight to understand the deformation behaviors of metals and alloys based on dislocation/disclination theory.
Article
Geochemistry & Geophysics
G. D. Tolometti, T. M. Erickson, G. R. Osinski, C. Cayron, C. D. Neish
Summary: This study analyzes four different samples from the Mistastin impact structure in Canada, revealing heterogeneity of superheated conditions in impact structures.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Peter A. Sharma, Taisuke Ohta, Michael T. Brumbach, Joshua D. Sugar, Joseph Michael
Summary: PEEM was used to investigate the surfaces of textured polycrystalline N-type bismuth telluride and P-type antimony telluride materials, showing changes in work function with exposure to air and the formation of oxide layers. The observed work function contrast is attributed to the pinning of electronic surface states due to defects at grain boundaries.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Nanoscience & Nanotechnology
Tomoaki Hamaguchi, Shinnosuke Kurihara, Hiroyuki Hirata, Hirokazu Okada
Summary: The study found that the creep strength of welded joints in 9Cr-3W-3Co-Nd-B steel is comparable to the base metal strength and ruptures in the heat-affected zone. The areas heated to around 1050 degrees Celsius are identified as the main cause of long-term rupture.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Chunguang Shen, Chenchong Wang, Minghao Huang, Ning Xu, Sybrand van der Zwaag, Wei Xu
Summary: The study introduces a deep learning method trained with electron backscattered diffraction (EBSD) that integrates traditional material characterization informatics and artificial intelligence to accurately classify and quantify complex microstructures using only SEM images. This method establishes a correlation between SEM input images and EBSD ground truth data for precise training, successfully applied to segment different phases and quantify phase content in engineering steels. The method demonstrates good generalization capabilities and robustness when applied to SEM images with varying states and imaging modes.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Geosciences, Multidisciplinary
John P. Platt, T. M. Mitchell, David J. Prior, Marianne Negrini, Sheng Fan, Mark Jefferd, Blaise Winnard
Summary: Research shows that grain-boundary migration (GBM) microstructures appear at low stress and high homologous temperature. Experimental results indicate that GBM microstructures have certain crystallographic characteristics, which may help determine paleostress.
JOURNAL OF STRUCTURAL GEOLOGY
(2022)
Article
Construction & Building Technology
Baozhen Jiang, Kotaro Doi, Koichi Tsuchiya
Summary: This study investigates the mechanical behavior of naturally generated corrosion products at the micro-scale level and discusses the influences of porosity, crystallinity, and grain size on their mechanical properties through microstructural characterization.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Junqing Han, Yuying Wu, Kai Zhao, Haoran Wang, Shushuai Liu, Xiangfa Liu
Summary: Cu foil was prepared with columnar grain growth and equiaxed grain growth with different average grain sizes by direct current electrodeposition. The correlation between the microstructures and properties of Cu foil under different grain growth methods was elucidated using EBSD, XRD, AFM, and TEM. The columnar-grown copper exhibited a remarkable preferential ratio of {220} orientation, while the equiaxed grain growth showed a superiority in {200} crystal orientation. The twin boundary density in copper foil increased as the grain growth mode changed, and grain refinement was beneficial to increase the twin boundary density.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Daniela Marusakova, Cinthia Antunes Correa, Claudia Aparicio, Ondrej Libera, Jan Berka, Monika Vilemova, Petra Gavelova
Summary: Nickel-based alloys, particularly Inconel 738, were tested in high-temperature gas reactor conditions to examine their performance in the primary helium coolant. Precision casting with different amounts of revert material was used to manufacture the alloys, and scanning electron microscopy and hardness testing were conducted to characterize the materials. The results showed that both revert materials exhibited similar corrosion resistance and mechanical properties in HTGR conditions.
Article
Nanoscience & Nanotechnology
Benjamin Poole, Fionn P. E. Dunne
Summary: In this study, slip activation, slip band interactions, and GND densities in the iron-based, galling resistant alloy Nitronic 60 were characterized at the grain length scale using small-scale mechanical testing with high resolution digital image correlation and high-angular resolution electron backscatter diffraction. Results show that multiple discrete slip bands are typically active within single grains, leading to slip band interactions, while crossing slip bands generate accumulations of high-density geometrically necessary dislocations (GNDs).
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Yuping Ren, Dongfang Lou, Mingda Zhang, Meiyuan Lv, Hongxiao Li, Gaowu Qin
Summary: This paper investigates the microstructure and mechanical properties of Zn-0.1Mg-1Mn alloy under different extrusion temperatures. The experimental results show that by controlling the extrusion temperature, the grain size and distribution of precipitates in the alloy can be changed, resulting in improved strength and ductility. This is of great significance for the development of biodegradable stents.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2023)
Article
Materials Science, Multidisciplinary
Brandon Leu, M. Arul Kumar, Kelvin Xie, Irene J. Beyerlein
Summary: A two-step growth mechanism for {101over line 2} tensile twins blocked by basal-precipitates in precipitate-hardened AZ91 magnesium alloy is proposed based on an elasto-viscoplastic fast-Fourier-transform (EVP-FFT) model. The stress fields resulting from the interaction of two sequentially propagated twins with a precipitate promote twin growth at the twin-precipitate junction. This mechanism explains the existence of thick twin domains in these material systems despite the hindrance of twin growth in precipitate-hardened Mg alloys.
Article
Materials Science, Multidisciplinary
Manish Jain, Krishna Yaddanapudi, Anugraha Thyagatur Kidigannappa, Kevin Baldwin, Marko Knezevic, Nathan A. Mara, Irene J. Beyerlein, Siddhartha Pathak
Summary: This work reports on the simultaneous improvements in both strength and mechanical stability of Nb/Mg nanolaminates with decreasing layer thicknesses, a trend seldom reported in nanolaminates consisting of pure metals. The presence of a body-centered cubic (bcc) Mg pseudomorphic phase in the nanolaminates results in an increase in strength by over 60% and an increase in strain to failure by over 80% compared to nanolaminates containing a hexagonal close-packed (hcp) Mg phase. The hcp-to-bcc phase transition in Mg leads to a renewed strengthening regime in the nanolaminate and an increase in strain-to-failure due to the change in interface coherence and the introduction of a more plastically isotropic bcc material.
Article
Materials Science, Multidisciplinary
Jonathan M. Hestroffer, Marie-Agathe Charpagne, Marat I. Latypov, Irene J. Beyerlein
Summary: This study introduces a graph neural network (GNN) approach for predicting mechanical properties of polycrystalline materials. The GNN model is developed based on graph representation of polycrystals, incorporating fundamental features of grains. The results show that the GNN accurately predicts stiffness and yield strength with a mean relative error of less than 1% for unseen microstructures and less than 2% for microstructures of unseen texture, even with limited training data.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
N. R. Brodnik, C. Muir, N. Tulshibagwale, J. Rossin, M. P. Echlin, C. M. Hamel, S. L. B. Kramer, T. M. Pollock, J. D. Kiser, C. Smith, S. H. Daly
Summary: Experimental solid mechanics is experiencing a crucial moment where the integration of machine learning (ML) approaches into the discovery process is rapidly increasing. The adoption of ML methods in mechanics originated from non-science and engineering applications, raising concerns about the reliability of the obtained physical results. To address this, it is necessary to incorporate physical principles into ML architectures, evaluate and compare them using benchmark datasets, and test their broad applicability. These principles allow for meaningful categorization, comparison, evaluation, and extension of ML models across various experimental and computational frameworks. Two different use cases, acoustic emission and resonant ultrasound spectroscopy, are examined to demonstrate the application of these principles and discussions are provided regarding the future prospects of trustworthy ML in experimental mechanics.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Nanoscience & Nanotechnology
Zezhou Li, Justin Y. Cheng, Jonathan D. Poplawsky, Shuozhi Xu, Jon K. Baldwin, Irene J. Beyerlein, Nathan A. Mara
Summary: In this study, the local chemistry of three-dimensional (3D) interfaces in Cu/Nb nanocomposites was characterized using atom probe tomography (APT). The analysis revealed chemical heterogeneities along all spatial dimensions in the 3D interfaces, established the length scale and morphology of these features. It was found that the heterogeneities in 3D interfaces form through surface diffusion during physical vapor deposition (PVD), indicating that deposition parameters can be used to control interface structure and explore processing-structure-property relationships in interface-dominated nanocomposites.
SCRIPTA MATERIALIA
(2023)
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
X. Z. Jin, C. Y. Wang, S. Milenkovic, I. Sabirov, I. J. Beyerlein, M. T. Perez-Prado
Summary: This study investigates the influence of solute segregation on the twin activity of aged Mg alloys. The authors examine the binary Mg-8Al alloy and two ternary Mg-8Al-1 Zn and Mg-8Al-1Ag alloys. They find that while the binary alloy shows no significant changes in twin activity after precipitation, the aged ternary alloys exhibit a drastic reduction in twin activity, possibly due to the decrease of particle-matrix interface energy caused by Zn and Ag segregation.
Article
Materials Science, Multidisciplinary
Jonathan M. Hestroffer, Jean-Charles Stinville, Marie-Agathe Charpagne, Matthew P. Miller, Tresa M. Pollock, Irene J. Beyerlein
Summary: This study investigates the incipient slip localization near hundreds of grain boundary triple junctions (TJs) in a lightly deformed nickel-base superalloy IN718 using a combination of three-dimensional (3D) crystal plasticity finite element modeling, high resolution digital image correlation, and 3D electron back-scatter diffraction tomography. The results show that TJs exhibit larger stress concentration and grain-average re-orientation compared to grain interiors and boundaries, but there are no substantial differences in cumulative slip among these microstructural regions.
Article
Materials Science, Multidisciplinary
Hong Liu, Fengxiang Lin, Nele Moelans, Liming Peng, Jian-Feng Nie, Irene J. Beyerlein
Summary: In this study, an analytical model is developed to predict the 3D shape and stress field of different-sized ellipsoidal twins in hexagonal close-packed metals. The model considers the effects of anisotropic twin boundary energy, elastic strain energy, and plastic relaxation. It is applied to Mg with a focus on a specific twin type. The results show that the stress field near structural defects facilitates the nucleation of nano-sized twin embryos, and the interplay between elastic strain energy and interfacial energy affects the length and stress distribution of the twin.
Article
Chemistry, Physical
Hui Zheng, Lauren T. W. Fey, Xiang-Guo Li, Yong-Jie Hu, Liang Qi, Chi Chen, Shuozhi Xu, Irene J. Beyerlein, Shyue Ping Ong
Summary: In this study, the influence of short-range ordering (SRO) on dislocation glide in MoNbTi and TaNbTi RMPEAs is investigated using a multi-scale modeling approach. The results show that MoNbTi exhibits a higher degree of SRO than TaNbTi, and the local composition directly affects the unstable stacking fault energies (USFEs). Increasing SRO leads to higher mean USFEs and stress required for dislocation glide. Gliding dislocations experience significant hardening due to pinning and depinning caused by random compositional fluctuations, with higher SRO decreasing the degree of USFE dispersion and amount of hardening. Lastly, the applied stress is shown to affect the morphology of an expanding dislocation loop.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Lauren T. W. Fey, Colleen Reynolds, Abigail Hunter, Irene J. Beyerlein
Summary: In this paper, a new phase-field dislocation dynamics formulation is presented to study the mechanical behavior of body-centered cubic (BCC) materials with interstitial solute atoms. Short-range and long-range interactions are accounted for by concentration-dependent lattice energy and modifications to the elastic energy. The diffusion of interstitials introduces gradients that are minimized using a modified Green's function. The method is applicable to any solute-solvent system and is applied to the NbO model system using interstitial parameters obtained from ab initio calculations. The effects of interstitial O on Nb edge and screw dislocation core structures are calculated, and the diffusion of O to form interstitial atmospheres around dislocation cores and the critical stresses required for dislocations to break away or cross slip from these atmospheres are simulated. Future applications of the method in studying complex interstitial embrittlement mechanisms are discussed.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Materials Science, Multidisciplinary
Irene J. Beyerlein, Penghui Cao, Tresa M. Pollock
Summary: Complex concentrated alloys (CCAs) are materials with three or more elements in similar proportions and lacking chemical long-range order. They have attracted attention in the past two decades and offer a new materials design paradigm for applications in aggressive environments. However, understanding their behavior is challenging due to the fluctuating chemical and structural variations at the atomic and nanoscales.
Article
Materials Science, Multidisciplinary
M. R. Jones, L. T. W. Fey, I. J. Beyerlein
Summary: In this work, a three-dimensional ab-initio informed phase-field-dislocation dynamics model combined with Langevin dynamics is used to investigate glide mechanisms of edge and screw dislocations in Nb at finite temperatures. It is found that the screw dislocation changes its mode of glide at two distinct temperatures, which coincides with the thermal insensitivity and athermal behavior of Nb yield strengths.
COMPUTATIONAL MATERIALS SCIENCE
(2024)
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.
