Article
Chemistry, Physical
Tongshan Lu, Jinpeng Lv, Chenghua Wang
Summary: Hydrogenation significantly improves the radiation stability of Ga2O3, while only slightly affects ZnO and TiO2. Oxygen deficient defects and grain size play vital roles in tuning the radiation tolerance of metal oxide semiconductors.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Analytical
Minkyung Lee, Hyun-Sook Lee, Min Young Kim, Kyu Hyoung Lee, Wooyoung Lee
Summary: This study provides experimental evidence that Li-ion implantation can improve the acetone sensing performance of ZnO-based sensors. The morphological structure of the sensors was controlled by Li-ion insertion/extraction, resulting in the generation of nanocracks that significantly enhanced the sensing performance. The nanocracked Ag-ZnO PNSs showed higher sensing response to acetone and remained stable at high temperatures.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Engineering, Electrical & Electronic
Jinpeng Lv, Xiangyu Wen, Zhenhua Zhou, Bo Zhou, Hexiang Han
Summary: This study systematically investigates the effects of O+ and N+ irradiation damage on ZnO bulk crystals, revealing the differences in ZnO damage induced by different ion irradiations. Our findings show that N+ irradiation results in a significant increase in electron concentration while O+ irradiation leads to the emergence of VZn related acceptors. Additionally, we observe the first observation of 450 nm VZn emission created by O+ irradiation.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
S. J. Jepeal, L. Snead, Z. S. Hartwig
Summary: The new technique of intermediate energy proton irradiation (IEPI) can rapidly damage bulk material specimens and simulate high dose rates, helping to accelerate the pace of engineering-scale radiation damage testing and advance the design of nuclear energy systems.
MATERIALS & DESIGN
(2021)
Article
Materials Science, Multidisciplinary
Joshua Ferrigno, Saqeeb Adnan, Marat Khafizov
Summary: As the burn-up of nuclear fuel increases, its thermal conductivity decreases due to the accumulation of defects, resulting in a rise in the centerline temperature of the fuel rod. Fuel performance codes based on established physical principles are limited in their predictive capabilities. Efforts are being made to develop predictive fuel performance codes and analyze the impact of point defects on thermal conductivity. Neglecting point defect concentration can lead to underestimation of the centerline temperature and potentially affect fission gas behavior.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Chemistry, Physical
J. Narayan, P. Joshi, J. Smith, W. Gao, W. J. Weber, R. J. Narayan
Summary: Q-carbon exhibits high resistance to radiation damage under ion irradiations, with its atomic structure and bonding characteristics remaining essentially unchanged. An ion-beam mixed layer containing a mixture of Al2O3 and Al4C3 forms below the Q-carbon layer after ion irradiations.
Article
Materials Science, Ceramics
M. T. P. Rigby-Bell, A. J. Leide, V. Kuksenko, C. J. Smith, G. Zilahi, L. Gale, T. Razzell, J. Wade-Zhu, D. J. Bowden
Summary: This study investigates the stability and microstructural evolution of SiCf/SiC composites through high-energy ion irradiation and annealing experiments. The results show that the material undergoes crystallographic evolution and exhibits phenomena such as stress and lattice swelling during irradiation. However, the fibers themselves remain stable without radiation-induced defects. During annealing, bubbles in the material grow and agglomerate, but no delamination or microcracking is observed.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2023)
Article
Materials Science, Multidisciplinary
Weon Cheol Lim, Jonghan Song, Tae-Yeon Seong, Keun Hwa Chae
Summary: This study investigates the modulation of lattice stress in ZnO thin films implanted with Ar, Mn and Ag ions. The results show that the granular nature of the films remains unchanged after ion implantation, but morphological changes are observed. The crystalline phase of the films remains unchanged at different doses of the ions, but lattice stress increases with the increase of ion implantation amount, which is difficult to explain using the ion radius. However, it is found to have a certain relationship with the total energy loss governed by both electronic and nuclear stopping process.
Article
Engineering, Electrical & Electronic
Tivadar Lohner, Attila Nemeth, Zsolt Zolnai, Benjamin Kalas, Alekszej Romanenko, Nguyen Quoc Khanh, Edit Szilagyi, Endre Kotai, Emil Agocs, Zsolt Toth, Judit Budai, Peter Petrik, Miklos Fried, Istvan Barsony, Jozsef Gyulai
Summary: Ion implantation is a key technology in microelectronics for controlled surface modification of materials. In this study, the formation and accumulation of shallow damage profiles in crystalline Ge during ion implantation were investigated using in-situ spectroscopic ellipsometry.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Review
Chemistry, Physical
Rosfayanti Rasmidi, Mivolil Duinong, Fuei Pien Chee
Summary: This paper provides a thorough review of the radiation effects on ZnO semiconductor devices, revealing changes in morphology, structure, optical and electrical parameters due to radiation exposure. The increase in ideality factor post-irradiation is attributed to recombination centers in the space charge region, indicating extrinsic recombination mechanisms involving lattice imperfections.
RADIATION PHYSICS AND CHEMISTRY
(2021)
Article
Chemistry, Physical
Q. Li, M. M. Yuan, M. D. Zhang, C. G. Guo, B. Liao, X. Zhang, M. J. Ying
Summary: The study demonstrates a strong ferromagnetism achieved by implanting Sm ions in ZnO films grown on sapphire substrates using MBE. Characterization techniques reveal differences in structure and magnetic properties between Zn-polar and O-polar films. After annealing, the magnetic moment of the O-polar film significantly decreases due to repair of grain boundaries and reduction of oxygen vacancies.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Engineering, Electrical & Electronic
Bo-Wen Lee, Jui-Chang Lin, Ruey-Dar Chang, Che-Men Chu, Wei -Yen Woon
Summary: In this study, subamorphizing implantation of phosphorus and hydrogen was used to investigate the donor activation behavior at low temperatures for the development of three-dimensional integrated circuits. It was found that the activation efficiency of phosphorus at 0 degrees implantation angle was higher than that at 7 degrees due to the broader defect and donor profiles. Hydrogen co-implantation at a dose of 1015 cm-2 enhanced the carrier concentration at 370 degrees C, but the enhancement decayed quickly and the carrier concentration at 400 degrees C was lower than that without hydrogen. The change in activation behavior suggested that the enhancement in carrier concentration was due to defect complexes generated by hydrogen implantation.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Jin-Jun Gu, Jin-Hua Zhao, Ming-Yang Bu, Su-Mei Wang, Li Fan, Qing Huang, Shuang Li, Qing-Yang Yue, Xue-Lin Wang, Zhi-Xian Wei, Yong Liu
Summary: This study investigates the radiation damage of 6H-SiC crystals through phosphorus ion implantation. The structure and optical properties of the crystals after P ion implantation were probed using Raman and absorption spectra. Furthermore, the damage behavior at different implantation energy and the evolution with post-annealing treatment were explored using Rutherford backscattering/channeling spectroscopy and transmission electron microscopy.
RESULTS IN PHYSICS
(2022)
Article
Crystallography
Tengfei Wu, Aiji Wang, Mingyu Wang, Yinshu Wang, Zilin Liu, Yiwen Hu, Zhenglong Wu, Guangfu Wang
Summary: In this study, the effects of ion irradiation on the properties of ZnO nanorods and their radiation resistance were investigated. The results showed that the pre-existing defects in the nanorods played a crucial role in the radiation effects, and the presence of an appropriate concentration of oxygen interstitials contributed to good radiation resistance.
Article
Energy & Fuels
Qianqian Yin, Linhui Si, Ruikun Wang, Zhenghui Zhao, Heping Li
Summary: This study investigated the adsorption properties of ammonium ions on defective carbonaceous surfaces using density functional theory. Factors such as the location and number of defect sites, as well as the presence of functional groups, were analyzed. The findings provide an important theoretical basis for the targeted modification of carbon materials for ammonium ion adsorption.
Article
Chemistry, Physical
Gibin George, Jacob Hayes, Candyce N. Collins, Jason E. Davis, Lei Yu, Yulin Lin, Jianguo Wen, Daryush Ila, Zhiping Luo
Summary: This study investigates the photoluminescence and cathodoluminescence characteristics of rare-earth-doped CaF2 nanoparticles and their composite monoliths with epoxy. The results show that the luminescence intensity increases as the particle size decreases for single-doped particles, but decreases for codoped particles. Additionally, Eu2+- and Tb3+-codoped CaF2 nanoparticles exhibit red emission.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Assel Aitkaliyeva
Summary: Metallic nuclear fuels have been extensively studied for over 60 years, showing distinctive irradiation behaviors compared to oxide fuels. Current gaps in understanding and recommendations for future research direction are identified for metallic U-Zr and U-Pu-Zr fuels. This review highlights key aspects of metallic fuel irradiation behaviors and points out areas for further research based on recent studies.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Charlyne A. Smith, Sudipta Biswas, Brandon D. Miller, Boopathy Kombaiah, David Frazer, Dennis D. Keiser, Assel Aitkaliyeva
Summary: This study used electron microscopy techniques and phase field modeling to investigate the mechanisms responsible for developing the high burnup structure in U-Mo fuels. The results show that grain subdivision is primarily initiated by polygonization, but dynamic recrystallization also occurs with increasing fission densities.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Kory Burns, Benjamin Bischoff, Christopher M. Barr, Khalid Hattar, Assel Aitkaliyeva
Summary: By utilizing infrared laser irradiation of free-standing MoS2 flakes in TEM, solid-state multi-level photoexfoliation of transition metal dichalcogenide quantum dots (QDs) is achieved, leading to high yield production. These findings provide an environmentally friendly synthesis method for fabricating QDs for potential applications in biomedicine, optoelectronics, and fluorescence sensing.
Article
Crystallography
Kory Burns, Paris C. Reuel, Fernando Guerrero, Eric Lang, Ping Lu, Assel Aitkaliyeva, Khalid Hattar, Timothy J. Boyle
Summary: The thermal and radiation stability of lanthanide-doped ceria nanoparticles were investigated, showing good thermal stability but tendency for amorphization under heavy ion irradiation. The impact of cation dopants on final nanoparticle properties was explored.
Article
Materials Science, Multidisciplinary
Gibin George, Navadeep Shrivastava, Tamela L. Moore, Caressia S. Edwards, Yulin Lin, Jianguo Wen, Zhiping Luo
Summary: In this study, high-aspect-ratio AWO(4) (A = Ba, Ca, Pb and Sr) nanofibers doped with Tb and Eu ions were synthesized and their performance in UV light detection was compared. The CaWO4:5Tb-5Eu nanofibers exhibited strong photoluminescence and cathodoluminescence emissions, making them a potential fluorescent probe for UV wavelength detection. However, similar results were not observed in nanofibers of other AWO(4) compounds. Additionally, the CL intensities from CaWO4:5Tb-5Eu nanofibers showed highly linear dependences on applied voltage and current, suggesting their potential use in radiation detection.
Article
Materials Science, Multidisciplinary
Menuka Adhikari, Navadeep Shrivastava, Starfari T. McClain, Chandra M. Adhikari, Burak Guzelturk, Rabi Khanal, Bhoj Gautam, Zhiping Luo
Summary: The halide Cs2HfF6 (CHF) possesses higher mass density and chemical stability for radiation detection compared to halides Cs2HfX6. Luminescence properties and energy transfer mechanisms of rare-earth-doped CHF materials are studied. Codoped CHF material shows stable emission and higher sensitivity to radiation energy.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Eric Lang, Kory Burns, Yongqiang Wang, Paul G. Kotula, Andrew B. Kustas, Sal Rodriguez, Assel Aitkaliyeva, Khalid Hattar
Summary: High-Entropy Alloys (HEAs) are proposed as materials for extreme environments, but the effects of radiation on their performance are not well understood. In this study, the response of additively manufactured refractory high-entropy alloys (RHEAs) to helium ion bombardment is investigated, revealing the interplay between alloy composition and helium bubble size and density.
Article
Materials Science, Multidisciplinary
Thaddeus Rahn, Brandon D. Miller, Luca Capriotti, Assel Aitkaliyeva
Summary: This article presents the microstructural examination of irradiated U-19Pu-10Zr fuel using selective area electron diffraction analysis. The results reveal the crystallographic information on the identified phases and highlight the importance of crystal structure in phase identification.
Article
Chemistry, Multidisciplinary
Girja Mani Aryal, Krishna Prasad Kandel, Ram Kumar Bhattarai, Basant Giri, Menuka Adhikari, Alisha Ware, Shubo Han, Gibin George, Zhiping Luo, Bhoj Raj Gautam, Bhanu Bhakta Neupane
Summary: In this study, multiple material properties of handmade Lokta paper from Nepal were measured and analyzed. The findings revealed that the papers are lightweight with intermediate to high strength, and the tensile strength is significantly higher along the length direction. Features of cellulose, hemicellulose, and lignin were observed in FTIR spectra, and crystalline and amorphous phases were identified in XRD data. Electron microscopy images showed a cross-linked network of fibers contributing to strength and durability.
Article
Materials Science, Multidisciplinary
C. M. Barr, E. Lang, K. Burns, P. Price, B. D. Miller, D. D. Keiser, A. Aitkaliyeva, K. Hattar
Summary: Nanoscale microstructural characterization of a U-10Mo/Zr barrier layer monolithic fuel plate was conducted using advanced transmission electron microscopy techniques to evaluate the microstructural changes after high burn-up. The study investigated the evolution of gas bubble superlattice, grain restructuring, and Zr inter-action layer through detailed electron microscopy characterization. The results revealed that the ultra-fine grains in irradiated U-10Mo fuel undergo restructuring and are separated by high angle grain boundaries at a burn-up of 4.42 x 10 21 fissions/cm3. Advanced chemical analysis and multi-variable statistical analysis also showed spatial clustering of solid fission product precipitates. Additionally, a newly observed porous nanocrystalline Zr region in the barrier layer was characterized. This work provides important insights into the grain subdivision and restructuring process in neutron-irradiated U-10Mo fuel using advanced microscopy techniques.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Casey McKinney, Floyd Hilty, Daniel Murray, Narayan Poudel, Fabiola Cappia, Tsvetoslav Pavlov, Assel Aitkaliyeva
Summary: The combination of microstructural characterization, property measurements, and phase field modeling was used to investigate the irradiation of FBR MOX fuel. The presence of grey phase in the central region depends on the nucleation of five metal precipitates. In addition, metal precipitates do not diffuse out of the mid-radial region once formed, and the size of Pd-Te precipitates is determined by the porosity in the region. Thermal conductivity measurements were conducted and correlated with the observed microstructure trend.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Suhas Eswarappa Prameela, Tresa M. Pollock, Dierk Raabe, Marc Andre Meyers, Assel Aitkaliyeva, Kerri-Lee Chintersingh, Zachary C. Cordero, Lori Graham-Brady
Summary: This viewpoint article discusses the importance of materials for extreme environments, and presents insights from experts in different fields regarding the most exciting advances, opportunities, and bottlenecks.
NATURE REVIEWS MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Kory Burns, Anne Marie Z. Tan, Jordan A. A. Hachtel, Anikeya Aditya, Nitish Baradwaj, Ankit Mishra, Thomas Linker, Aiichiro Nakano, Rajiv Kalia, Eric J. J. Lang, Ryan Schoell, Richard G. G. Hennig, Khalid Hattar, Assel Aitkaliyeva
Summary: Ultrathin MoS2 shows remarkable characteristics at the atomic scale and is resistant to weak external stimuli. Ion beam modification can selectively adjust the size, concentration, and morphology of defects in 2D materials. By combining experiments, calculations, simulations, and transfer learning, this study demonstrates that irradiation-induced defects can create a rotation-dependent moire pattern and surface acoustic waves in vertically stacked homobilayers of MoS2. The direct correlation between stress and lattice disorder is also demonstrated. This research sheds light on the engineering of defects to tailor the angular mismatch in van der Waals solids.
Article
Materials Science, Multidisciplinary
Kasci D. Pelucarte, Tashi A. Hatchell, Gibin George, Sivasankara Rao Ede, Menuka Adhikari, Yulin Lin, Jianguo Wen, Zhiping Luo, Shubo Han
Summary: In this study, porous La-Sr-Co-Ni-O nanofibers with a perovskite structure were successfully prepared and utilized to develop a nonenzymatic electrochemical glucose biosensor. The biosensor exhibited high sensitivity and excellent stability towards glucose, while showing low interference response to other biomolecules. This research has great potential for practical applications in clinical testing.
MATERIALS ADVANCES
(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.
