Article
Materials Science, Multidisciplinary
Nicolas J. Peter, Maria J. Duarte, Christoph Kirchlechner, Christian H. Liebscher, Gerhard Dehm
Summary: Experimental results show that the isothermal nanofacet evolution occurs at an asymmetric Sigma 5 tilt grain boundary in the Cu-Ag system, where the excess of Ag solute affects the length of Ag-rich facet segments, while the length of asymmetric facets remains constant. A grain boundary nanofaceting diagram constructed from experimental data explains the relationship between local atomic structure, overall inclination, and Ag solute excess.
Article
Chemistry, Physical
Anastasia V. Mikhaylovskaya, Olga A. Yakovtseva, Andrey G. Mochugovskiy, Joan Cifre, Igor S. Golovin
Summary: The influence of a minor addition of Zn on the superplastic properties of Al-Mg alloys was investigated. It was found that the addition of a small amount of Zn can promote grain boundary sliding, resulting in increased strain rate sensitivity and elongation-to-failure of the alloy.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
Dianguang Liu, Kewei Wang, Ke Zhao, Jinling Liu, Linan An
Summary: This study systematically investigated the tensile creep of 3 mol% Y2O3 stabilized tetragonal ZrO2 ceramics under a DC field. The results showed that the deformation mechanism of the material strongly depended on the current density and applied stress. Exceptionally large uniform elongation can be obtained when the creep is dominated by dislocation accommodated grain-boundary sliding.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
Phillip Dumitraschkewitz, Matheus A. Tunes, Cameron R. Quick, Diego Santa Rosa Coradini, Thomas M. Kremmer, Parthiban Ramasamy, Peter J. Uggowitzer, Stefan Pogatscher
Summary: The solidification behavior of a eutectic AlCu specimen is investigated using in situ scanning transmission electron microscope experiments. By varying the cooling conditions, different rapid solidification morphologies are obtained. Additionally, the spheroidization of lamellas during annealing at elevated temperatures is studied.
Article
Nanoscience & Nanotechnology
Anastasia V. Mikhaylovskaya, Olga A. Yakovtseva, Natalia Yu. Tabachkova, Terence G. Langdon
Summary: During superplastic deformation of microduplex-structured brasses, strain primarily occurs in the beta-phase through grain boundary sliding and dislocation slip/creep mechanisms. Dynamic recrystallization and twinning transform the initial coarse beta-phase grains into ultrafine grains, and alloying with Al improves superplastic behavior and reduces residual cavitation.
SCRIPTA MATERIALIA
(2022)
Article
Nanoscience & Nanotechnology
Liujie Yang, Xingyu Feng, Jiayu Xie, Hongchen Qian, Xianchao Hao, Wenjun Kuang
Summary: The grain boundary corrosion behavior of Ni15Cr alloy in 650°C/1bar CO2 gas was investigated. It was found that the oxidation behavior of coherent twin boundary is similar to that of grain matrix, while the incoherent twin boundary is prone to preferential intergranular oxidation. Low angle GB is also susceptible to intergranular oxidation, although it can induce GB migration and result in a protective scale. In contrast, random high angle GB is immune to intergranular oxidation.
SCRIPTA MATERIALIA
(2022)
Review
Materials Science, Multidisciplinary
Roberto B. Figueiredo, Megumi Kawasaki, Terence G. Langdon
Summary: The grain size and grain boundary density have significant effects on the flow stress of metallic materials. The Hall-Petch grain refinement strengthening effect, which is a linear relationship to the inverse of the square root of the grain size, has been well-established for more than 70 years. However, grain refinement softening can occur at high homologous temperatures and both effects have been treated separately. Recent research has shown that a general relationship can explain both the Hall-Petch strengthening effect at low temperatures and superplasticity at high temperatures. This review discusses recent advances in structural and mechanical characterization and provides an updated analysis of the relationship between grain size and flow stress.
PROGRESS IN MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Qing Zhang, Xiaofei Ju, Jun Liu, Lei Wang, Yang Li, Haowei Wang, Zhe Chen
Summary: The addition of TiB2 nanoparticles as reinforcement in Al-Zn-Mg-Cu composite leads to the formation of fine-equiaxed grains, which enhances both the elongation and thermal stability of the material. The deformation at grain boundaries is controlled by grain boundary sliding mechanism, and the stress release and prevention of cavitation are facilitated by locally melted Mg-rich phases.
MATERIALS CHARACTERIZATION
(2021)
Article
Nanoscience & Nanotechnology
Zeinab Savaedi, Hamed Mirzadeh, Rouhollah Mehdinavaz Aghdam, Reza Mahmudi
Summary: Shear punch testing was used to evaluate the superplasticity of a hot rolled fine-grained Mg-3Zn-0.5RE-0.5Zr (ZEK300) alloy. The alloy exhibited regions I, II, and III of deformation behavior typical of superplastic materials, with a grain size of 4.5 μm. In region II, the strain rate sensitivity indices of the ZEK300 alloy were determined to be 0.51, 0.48, and 0.41 at temperatures of 350, 400, and 450 degrees C, respectively. The average activation energy of 87.6 kJ mol-1 suggests that grain boundary sliding (GBS) facilitated by grain boundary diffusion is the dominant deformation mechanism.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Metallurgy & Metallurgical Engineering
A. Rezaei, R. Mahmudi, R. E. Loge
Summary: The microstructure of the extruded Mg-6Gd-3Y-1.5Ag alloy was refined through ECAP processing, resulting in improved superplastic behavior.
JOURNAL OF MAGNESIUM AND ALLOYS
(2023)
Article
Chemistry, Physical
Hyun-Bin Jeong, Jin-Young Lee, Ju-Chan Jin, Hyung-Jin Cho, Young-Kook Lee
Summary: In this study, a Fe-Mn-Si-Ni steel was developed to exhibit superplasticity at a low temperature and a high strain rate, while maintaining remarkable room-temperature tensile strength and total elongation. The excellent superplasticity was achieved by grain boundary sliding at the boundaries of fine gamma grains, which were prevented from coarsening by Fe5(Mn,Ni)3Si2 and (Fe,Mn,Ni)3Si precipitates.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Jianheng Cai, Hua Wang, Cheng Qiu, Genghua Cao, Datong Zhang
Summary: ZK60 magnesium alloy is refined through submerged friction stir processing (SFSP), leading to the observation of high-strain-rate superplasticity (HSRS) at elevated temperature. The excellent HSRS is attributed to the uniform fine-grained structure and the relatively high fraction of high-angle grain boundaries, which facilitate grain boundary sliding. Additionally, the presence of dispersed fine particles/precipitates enhances the microstructural stability of the specimens.
ADVANCED ENGINEERING MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Kai Li, Dongyang He, Hailang Liu, Zhuangzhi Wu, Dezhi Wang
Summary: A new additive, LaB6, was proposed to enhance the mechanical properties of Mo-based alloys by reacting with the matrix to generate coherent La2O3, volatile B2O3 and tiny MoB in situ. The addition of LaB6 limits grain growth and constructs a coherent interface between La2O3 and Mo matrix. Moreover, the oxygen impurity is removed by B in the form of B2O3, purifying the grain boundaries and resulting in an extremely high ultimate tensile strength of 965 MPa for the Mo-La-B billets.
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
A. Rezaei, R. Mahmudi, C. Cayron, R. E. Loge
Summary: In this study, a Mg-6Gd3Y-0.5Ag magnesium alloy was processed using simple shear extrusion (SSE) technique to refine its microstructure. The research found that continuous dynamic recrystallization was the dominant recrystallization mechanism, and the alloy processed with 6 SSE passes exhibited superplastic flow, with grain boundary sliding being the prevalent deformation mechanism.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Frank Niessen, Azdiar A. Gazder, David R. G. Mitchell, Elena V. Pereloma
Summary: Microstructure evolution during the 3-point bending of a metastable beta Ti-10V-2Fe-3Al alloy containing 5% alpha was dominated by the formation of deformation-induced alpha '' martensite. The nucleation of alpha '' plates from {580}(alpha '') habit planes at alpha-beta interfaces, impingement with high-angle boundaries, and subsequent thickening led to a build-up of strain energy inducing {130} < 310 >(alpha '') twinning. The study also revealed the activation of {130}< 310 >(alpha '') twinning by alpha '' impingement in a metastable beta matrix.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Orthopedics
Logan Windell, Ashwin Kulkarni, Enrique Alabort, Daniel Barba, Roger Reed, Harvinder P. Singh
Summary: The research compared the biomechanics of different types of hip arthroplasty implants in a composite model, finding that the CPT and C-Stem implants fractured at lower rotation and torque values and with less comminution. Therefore, the CPT implant carries a higher risk of PPFs.
JOURNAL OF ARTHROPLASTY
(2021)
Article
Materials Science, Multidisciplinary
Carmen Torres-Sanchez, James M. Borgman, Ben Sargeant, Hugo Bell, Enrique Alabort, Craig Lindsay, Paul P. Conway
Summary: This study compared the effects of different support structures on the parameter design of tissue engineering scaffolds, as well as the impact of topology on compressive properties and osteoblastogenesis. Considerations were made for discrepancies between design intent and manufactured products to ensure consistency in important factors like porosity and surface area per unit volume.
ADVANCED ENGINEERING MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Lola Lilensten, Aleksander Kostka, Sylvie Lartigue-Korinek, Baptiste Gault, Sammy Tin, Stoichko Antonov, Paraskevas Kontis
Summary: Solute partitioning in Cr-rich M2B borides at crystal defects was investigated after creep and annealing in a nickel-based superalloy. Coarsening of borides was observed in both cases, with the coarsened borides after creep being the thickest. The presence of a high density of planar faults and chemical fluctuations of B and Cr within the coarsened borides were revealed by transmission electron microscopy and atom probe tomography.
Article
Materials Science, Multidisciplinary
Arthur Despres, Stoichko Antonov, Charlotte Mayer, Catherine Tassin, Muriel Veron, Jean-Jacques Blandin, Paraskevas Kontis, Guilhem Martin
Summary: The study investigates the relationship between hot cracking susceptibility and creep resistance in a nickel-based superalloy with different contents of boron, carbon and zirconium. By analyzing the distribution of these elements at grain boundaries, the research reveals the importance of alloy design guidelines for achieving both crack-free fabrication and required creep performance after heat-treatment. The presence or absence of specific elements at grain boundaries plays a crucial role in determining the alloy's properties.
Article
Materials Science, Multidisciplinary
E. Alabort, Y. T. Tang, D. Barba, R. C. Reed
Summary: This study utilizes an alloy design approach to identify biocompatible titanium alloy compositions with a lower modulus of elasticity than the commonly used Ti-6Al-4V grade. The study also considers the additive manufacturability of the alloys and identifies compositions with low cracking susceptibility and propensity for non-planar growth. An optimal alloy composition is selected for selective laser melting, resulting in an engineered microstructure with outstanding combined strength and ductility.
Article
Engineering, Biomedical
C. Torres-Sanchez, E. Alabort, J. Wang, M. Norrito, P. P. Conway
Summary: The numerical design of the TiNbTaZrMoSn alloy was conducted before its manufacture to predict its performance, and the experimental results were found to be in good agreement with the predictions. The study highlighted the importance of oxide layer thickness and surface potential in osteogenic activity, while cell adhesion and viability were less affected. The TiNbTaZrMoSn alloy showed slightly lower osteogenic properties compared to c.p. Titanium due to its thinner oxide layer and lower surface potential.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2021)
Article
Multidisciplinary Sciences
Yuan Wu, Di Cao, Yilin Yao, Guosheng Zhang, Jinyue Wang, Leqing Liu, Fengshou Li, Huiyang Fan, Xiongjun Liu, Hui Wang, Xianzhen Wang, Huihui Zhu, Suihe Jiang, Paraskevas Kontis, Dierk Raabe, Baptiste Gault, Zhaoping Lu
Summary: By introducing dense local packing regions in BMGs, enhancing structural fluctuations has led to a simultaneous increase in ductility and strength.
NATURE COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Sudha Joseph, Paraskevas Kontis, Yanhong Chang, Yitong Shi, Dierk Raabe, Baptiste Gault, David Dye
Summary: This study investigates the presence of oxygen and hydrogen at crack tips in an industrial titanium alloy. The results show that crack tips are enriched in oxygen, while the amount of hydrogen is relatively low. The authors suggest that the combined effect of oxygen and hydrogen leads to cracking, with oxygen playing a vital role in embrittlement.
Article
Nanoscience & Nanotechnology
Hanna Bishara, P. Kontis, Gerhard Dehm, Jochen M. Schneider, Simon Evertz
Summary: The relationship between the fraction of hybridized bonds and the electrical behavior in thin film metallic glasses has been investigated. It was found that strong bond hybridization leads to high resistivity, while weak bond hybridization results in lower resistivity.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
Jinghao Xu, Paraskevas Kontis, Ru Lin Peng, Johan Moverare
Summary: This study investigates the additive manufacturability of nickel-based superalloys for laser powder bed fusion (LPBF) technologies by considering the in-process cracking mechanisms. A two-parameter-based model, called heat resistance and deformation resistance (HR-DR) model, is proposed to predict the cracking susceptibility of nickel-based superalloys during LPBF. The model is validated through LPBF experiments and compared with reported data in the LPBF superalloys community. The model provides insights into the influence of alloying elements and gamma' precipitates on the additive manufacturability and offers a pathway for designing new solid solutioning and gamma' strengthened nickel-based superalloys for LPBF applications.
Article
Materials Science, Multidisciplinary
Malik Durand, Jonathan Cormier, Fabien Paumier, Shyam Katnagallu, Aparna Saksena, Paraskevas Kontis, Florence Pettinari-Sturmel, Muriel Hantcherli, Jean-Michel Franchet, Christian Dumont, Nathalie Bozzolo
Summary: The present study aims to understand the mechanisms of macroscopic contraction in gamma/gamma' nickel based superalloys during isothermal annealing. The study characterized AD730 (TM) alloy samples using various methods and found that chemical composition changes during annealing led to a decrease in lattice parameters and resulted in macroscopic volume contraction.
Article
Nanoscience & Nanotechnology
Aparna Saksena, Dorota Kubacka, Baptiste Gault, Erdmann Spiecker, Paraskevas Kontis
Summary: This article investigates the effects of high-temperature diffusion on the long-term stability and service life of superalloys, and reveals a width-dependence in compositional evolution. The findings have significant implications for microstructural and compositional predictions of superalloy service life.
SCRIPTA MATERIALIA
(2022)
Review
Materials Science, Multidisciplinary
J. Tjandra, E. Alabort, D. Barba, S. Pedrazzini
Summary: This paper examines the corrosion, fatigue, and wear properties of AM Ti alloys to ensure their safety in orthopedic implants. It specifically highlights the lattice structures of AM Ti due to their improved osseointegration and better modulus matching with bone, making them an attractive option for durable implant devices. The properties of current AM implants are also compared to those made via conventional manufacturing methods to confirm their overall safety.
MATERIALS SCIENCE AND TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Stoichko Antonov, Arthur Despres, Charlotte Mayer, Guilhem Martin, Paraskevas Kontis
Summary: This study investigated the segregation of solutes at dislocations in a nickel-based superalloy produced by laser powder bed fusion. High density of dislocations was observed in the as-built microstructure, which was reduced after a subsolvus heat treatment but not completely eliminated. Boron segregation at dislocations in the & gamma; matrix was found in the as-built state, both in the interdendritic and dendritic core region, as well as near grain boundaries. Molybdenum, carbon, and tungsten were also found to segregate at dislocations in the & gamma; matrix. The segregation behavior of remaining dislocations in the & gamma; matrix was not altered after the subsolvus heat treatment, but higher amounts of boron, molybdenum, and tungsten were observed compared to the as-built state. The implications of boron trapping at dislocations in additively manufactured superalloys are briefly discussed.
Article
Materials Science, Multidisciplinary
A. Cardena, R. Sancho, D. Barba, F. Galvez
Summary: The dynamic behavior of additively manufactured Ti6Al4V lattice-based BCC structures is studied in this research by varying the strut diameter and applying a standard heat treatment. The strut diameter shows a strong dependence on the strength, toughness, and failure mode of the lattice.
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.
