Article
Materials Science, Multidisciplinary
Zhiguo Zhang, Chuangnan Wang, Billy Koe, Christian M. Schleputz, Sarah Irvine, Jiawei Mi
Summary: High speed synchrotron X-ray imaging and ultrafast tomography were used to study the fragmentation and growth dynamics of dendritic microstructures in an Al-15%Cu alloy under ultrasound. The results showed that efficient dendrite fragmentation occurred due to the acoustic flow, with thermal perturbation remelting plus mechanical fracture and separation being the dominant mechanism, while acoustic flow fatigue impact and phase collision effects played a minor role. Ultrasound application in the early solidification stage for just 10 s led to a significant increase in dendrite fragment number.
Article
Materials Science, Multidisciplinary
Xudong Liu, Qingfeng Zhu, Cheng Zhu, Yubo Zuo, Haichang Jiang
Summary: This study investigated the mechanisms involved in the grain refinement of a 2024 aluminum alloy prepared through the direct-chill (DC) casting process with the introduction of intensive melt shearing. The experiments and theoretical analyses demonstrated that shear stress between the stator and rotor can break the dendrite arms. The experimental results showed that the cooling rate of the melt during intensive melt shearing casting is higher than that in conventional DC casting, leading to improved grain refining effect when shearing is processed at a lower position with a higher rotation speed.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Insung Han, Shikang Feng, Fabian Wilde, Patrick S. Grant, Enzo Liotti
Summary: Hot tears during alloy solidification can have catastrophic effects on cast tensile properties. While there are correlations between casting conditions and hot tear sensitivity, the influence of microstructure on tearing has not been fully understood. In this study, in situ X-ray radiography is used to quantify the formation and growth of hot tears in Al-5Cu and Al-5Cu-1Fe alloys, and an automated hot tear detection algorithm is developed to analyze the role of IMC particles in hot tear behavior.
Article
Metallurgy & Metallurgical Engineering
Ling Qin, Zhiguo Zhang, Baisong Guo, Wei Li, Jiawei Mi
Summary: In this study, in situ synchrotron X-ray radiographic and tomographic imaging techniques were combined to evaluate the critical fracture stress of growing dendrites during the solidification of an Al-15 wt% Cu alloy. Two dendritic 3D models were proposed to simulate the morphologic characteristics and revealed that the critical fracture stresses of the Al dendrites were in the range of 0.5 kPa-0.05 MPa. These results demonstrate the feasibility of measuring the high-temperature mechanical properties of metallic dendrites.
ACTA METALLURGICA SINICA-ENGLISH LETTERS
(2023)
Article
Chemistry, Physical
Shuo Wang, Zhipeng Guo, Jinwu Kang, Meishuai Zou, Xiaodong Li, Ang Zhang, Wenjia Du, Wei Zhang, Tung Lik Lee, Shoumei Xiong, Jiawei Mi
Summary: This paper studied the dynamics of multi-dendrite concurrent growth and coarsening of an Al-15 wt.% Cu alloy using a highly computationally efficient 3D phase field model and real-time synchrotron X-ray micro-tomography. The results indicated that the multi-dendrite coarsening mechanisms obey the Lifshitz-Slyozov-Wagner theory with a higher constant of n = 4.3.
Article
Materials Science, Multidisciplinary
L. Abou-Khalil, Z. Thompson, G. Reinhart, T. Stan, L. Sturz, G. Zimmermann, P. W. Voorhees, N. Mangelinck-Noel, H. Nguyen-Thi
Summary: Three-dimensional reconstruction of the microstructure of Al - 7 wt.% Si samples solidified in microgravity conditions on the International Space Station revealed that the number of dendrite fragments depends on the dendrite network configuration. Samples with multiple dendrites with different orientations had more fragments compared to samples with well-aligned dendrites. The highest number of fragments was found in the region corresponding to an incipient grain boundary where dendrites with different orientations compete, indicating that dendrite misorientation during solidification leads to the formation of dendrite fragmentation.
Article
Materials Science, Multidisciplinary
Jia Liu, Jinchuan Jie, Xianlong Wang, Shumin Lou, Bo Peng, Tingju Li
Summary: The effect of pulsed magnetic field on the solidification structure of aluminum was investigated in this study. The results showed that applying the magnetic field led to the formation of a refined equiaxed grain layer, which is important for understanding the evolution of solidification structure.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2022)
Article
Nanoscience & Nanotechnology
Tomoya Nagira, Terumi Nakamura, Fumiyoshi Yoshinaka, Takahiro Sawaguchi, Yasuhiro Aoki, Masayoshi Kamai, Hidetoshi Fujii, Akihisa Takeuchi, Masayuki Uesugi
Summary: In this study, the dendrite-scale microstructural evolution of Fe-Mn-Si alloys during TIG spot welding was observed using high-spatial resolution X-ray imaging and diffraction. The solidification mode was found to significantly influence the susceptibility to solidification cracking.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
Yuliang Zhao, Weixiang He, Dongfu Song, Weiwen Zhang, Fanghua Shen, Baisheng Ma, Yiwang Jia, Zhenzhong Sun, Yanan Fu, Ricardo Fernandez
Summary: The influence of cooling rate on the nucleation and growth of primary Fe-rich phases during solidification of Al-Fe(-Cu) alloy has been studied. It was found that the total number and number density of primary Fe-rich phases are similar at cooling rates of 0.1°C/s and 1.0°C/s, but increase by 300% at a cooling rate of 0.5°C/s. The addition of Cu and higher cooling rates result in constitutional undercooling and promote the formation of refined primary Al3Fe particles.
MATERIALS CHARACTERIZATION
(2023)
Article
Materials Science, Multidisciplinary
Piotr Mikolajczak
Summary: The study investigated the solidification of AlCuSi alloys with Mn and Fe under the influence of a rotating magnetic field, showing that forced convection helps decrease secondary dendrite arm spacing and length of harmful β-Al5FeSi phases. Additionally, equiaxed dendrites undergo a morphology transformation during this process. Overall, flow has a significant impact on the properties of the alloys.
Article
Nanoscience & Nanotechnology
Ryoji Katsube, Litian Luo, Keita Nakano, Taka Narumi, Hideyuki Yasuda
Summary: The solidification sequence of the CrMnFeCoCu alloy, a multicomponent and multiphase alloy derived from the CrMnFeCoNi alloy, was investigated. It was found that the microstructure of this alloy formed through a process of liquid-liquid phase separation and subsequent solid-phase transformation, rather than the conventional multiphase solidification manner. The understanding of these processes can contribute to the control of microstructure in multicomponent and multiphase alloys.
SCRIPTA MATERIALIA
(2023)
Article
Astronomy & Astrophysics
Lukasz Farbaniec, David J. Chapman, Jack R. W. Patten, Liam C. Smith, James D. Hogan, Alexander Rack, Daniel E. Eakins
Summary: The study investigated the relationship between the dynamic mechanical properties of stony meteorites and their microstructures using advanced imaging techniques and microCT analysis. It validated and explained the fragmentation process in meteorites, providing insights into impact-induced fragmentation processes that have shaped the solar system.
Article
Materials Science, Multidisciplinary
Nagasivamuni Balasubramani, Yanyi Xu, Yunhu Zhang, Qijie Zhai, Gui Wang, David StJohn, Matthew Dargusch
Summary: A comparison study on the solidification of pure Al using electric current in the pulsed mode (ECP), ultrasonic treatment (UST), and melt stirring treatment (MST) revealed that UST outperformed ECP in all temperature ranges, while MST showed comparable refinement to UST at a specific temperature. The techniques differ in terms of the dominant mechanism influencing grain refinement, with UST showcasing the best results overall.
Article
Materials Science, Multidisciplinary
Xintian Liu, Yaqing Sun, Yongbiao Wang, Sensen Jia, Yujuan Wu, Liming Peng, Jianglei Fan, Ying Li, Jianxiu Liu, Ansheng Li
Summary: The solidification process of Mg-15Gd alloys with different cross-section geometry was investigated using synchrotron radiation imaging technology. The evolution of dendrites, including nucleation and growth processes, was recorded and analyzed. The results show that the cross-section geometry of the samples has a significant effect on the number and growth rate of dendrites, as well as solute distribution.
MATERIALS CHARACTERIZATION
(2022)
Article
Nanoscience & Nanotechnology
D. Schimbaeck, P. Mair, M. Baertl, F. Palm, G. Leichtfried, S. Mayer, P. J. Uggowitzer, S. Pogatscher
Summary: To fully exploit the potential of additive layer manufacturing, adapting materials to the process via smart alloy design is necessary. Different microstructural evolutions were studied in Sc-modified Al alloys with the addition of Mg, Cr, or Ti as main elements. The differences in microstructures arise from interactions of grain growth restriction factors and solute with the primary precipitation structure.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
E. Liotti, A. Lui, T. Connolley, P. S. Grant
Summary: This study investigates the importance of controlling shrinkage-induced liquid flow and hot tear formation in alloy castings during the final stages of solidification. Experimental measurements using synchrotron X-rays are conducted to track and measure the velocity of liquid metal droplets and estimate the interdendritic liquid velocity and shrinkage pressure drop. The results are consistent with prior model-based and theoretical suggestions.
Article
Materials Science, Multidisciplinary
S. Zhao, Y. Chen, L. Saucedo-Mora, T. Connolley, T. J. Marrow
Summary: This study aims to develop a novel methodology for measuring the deformation of ceramic composite tubes. By observing the burst test of SiC/SiC composite tubes using high resolution X-ray tomography and measuring the three-dimensional displacements using digital volume correlation, the results regarding strain and cracking were obtained.
EXPERIMENTAL MECHANICS
(2023)
Article
Materials Science, Multidisciplinary
Sophie A. M. McNair, Jiraphant Srisuriyachot, Samuel Omole, Thomas Connolley, Andrew Rhead, Alexander J. G. Lunt
Summary: Small-diameter, thin-walled pipes are widely used in industries such as high-energy physics, heat transfer, nuclear, medical, and communications. The performance of thin-walled pipe welds less than 0.5 mm in width is difficult to determine due to the lack of existing standards. Porosity is a determining factor in the performance of the connection. This study found that reducing residual stresses is more important than reducing porosity for improving weld strength.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Chemistry, Physical
Chu Lun Alex Leung, Matthew D. Wilson, Thomas Connolley, Stephen P. Collins, Oxana Magdysyuk, Matthieu N. Boone, Kosuke Suzuki, Matthew C. Veale, Enzo Liotti, Frederic Van Assche, Andrew Lui, Chun Huang
Summary: Increasing electrode thickness is considered as a potential method to improve energy density in Li ion batteries. However, the diffusion of Li+ ions during (dis)charge, especially at higher rates, limits the realizable capacity and rate capability. Visualizing and quantifying Li+ chemical stoichiometry distribution inside the electrode within commercially standard battery geometry is still challenging. In this study, the distribution of Li+ chemical stoichiometry in the electrode microstructure of a working coin cell battery is mapped using innovative in situ correlative full-field X-ray Compton scattering imaging (XCS-I) and X-ray computed tomography (XCT).
MATERIALS TODAY ENERGY
(2023)
Article
Nanoscience & Nanotechnology
Ruihuan Ge, Adam M. Boyce, Yige Sun, Paul R. Shearing, Patrick S. Grant, Denis J. Cumming, Rachel M. Smith
Summary: The complex microstructure of the electrode greatly affects the performance of lithium-ion batteries (LIBs). The microporosity of the carbon binder domain (CBD) has been studied for the first time, revealing its influence on battery performance. The battery's specific capacity improves as the microporosity of the CBD phase increases.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Engineering, Mechanical
A. Koko, S. Singh, S. Barhli, T. Connolley, N. T. Vo, T. Wigger, D. Liu, Y. Fu, J. Rethore, J. Lechambre, J. -Y. Buffiere, T. J. Marrow
Summary: The propagation rate of a fatigue crack in a nodular cast iron was studied using X-ray computed tomography and digital volume correlation. The crack evolved from an asymmetric corner notch and showed a higher growth rate on one side before becoming independent of position. Crack shape was measured using phase congruency of displacement field. Three-dimensional stress intensity factors were calculated using a linear elastic finite element model. The cyclic change in local mode I opening determined the fatigue crack propagation rate along the crack front.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Materials Science, Multidisciplinary
Shikang Feng, Zelong Jin, Wenjia Du, Insung Han, Andrew Lui, Xiaorong Zhou, Paul R. Shearing, Enzo Liotti, Patrick S. Grant
Summary: Fe-rich intermetallics have a significant impact on the mechanical properties and recyclability of aluminium alloys. This paper investigates the formation and growth mechanisms of primary Al13Fe4 on Al3Ti inoculants through various analytical techniques. The study reveals the crystallographic orientation relationships between Al13Fe4 and Al3Ti, as well as the correlation between the formation and growth dynamics of Al13Fe4 and a twinning-related pseudo-symmetry of Al13Fe4. A potential strategy to refine both intermetallics and a-Al in recycled alloys with elevated Fe concentration is proposed.
MATERIALS & DESIGN
(2023)
Article
Multidisciplinary Sciences
Ziyang Ning, Guanchen Li, Dominic L. R. Melvin, Yang Chen, Junfu Bu, Dominic Spencer-Jolly, Junliang Liu, Bingkun Hu, Xiangwen Gao, Johann Perera, Chen Gong, Shengda D. Pu, Shengming Zhang, Boyang Liu, Gareth O. Hartley, Andrew J. Bodey, Richard I. Todd, Patrick S. Grant, David E. J. Armstrong, T. James Marrow, Charles W. Monroe, Peter G. Bruce
Summary: All-solid-state batteries with a Li anode and ceramic electrolyte have the potential to significantly outperform current Li-ion batteries. However, the formation and penetration of Li dendrites during charging remain a major challenge. Previous models focused on a single process for dendrite initiation and propagation, but our study reveals that these processes are actually separate and independent.
Article
Engineering, Manufacturing
Tristan G. Fleming, David Tien Rees, Sebastian Marussi, Thomas Connolley, Robert C. Atwood, Martyn A. Jones, James M. Fraser, Chu Lun Alex Leung, Peter D. Lee
Summary: Directed energy deposition (DED) is a promising additive manufacturing technique for repair, but it is prone to surface waviness and cracking in thin-walled sections. The crack formation mechanism in DED is not well understood due to a lack of monitoring methods. In this study, inline coherent imaging (ICI) was used to optically monitor surface topology and detect cracking in situ.
ADDITIVE MANUFACTURING
(2023)
Article
Chemistry, Physical
Dominic Spencer-Jolly, Varnika Agarwal, Christopher Doerrer, Bingkun Hu, Shengming Zhang, Dominic L. R. Melvin, Hui Gao, Xiangwen Gao, Paul Adamson, Oxana Magdysyuk, Patrick S. Grant, Robert A. House, Peter G. Bruce
Summary: Ag-carbon composite interlayers have been proven effective in enabling Li-free cycling of solid-state batteries. Li intercalates electrochemically into graphite on charge, subsequently reacting chemically with Ag to form Li-Ag alloys. Discharge does not reverse this process, instead passing through Li-deficient Li-Ag phases. At higher charging rates, Li intercalation outpaces chemical reactions with Ag, resulting in delayed Li-Ag phase formation and increased Li metal deposition at the current collector. Li dendrites are not suppressed at and above 2.5 mA•cm-2, and Ag nanoparticles are not more effective than a graphite interlayer. Instead, Ag in the carbon interlayer promotes more uniform Li and Li-Ag formation during charge.
Article
Chemistry, Physical
Sang Ho Lee, Yige Sun, Patrick S. Grant
Summary: This research developed an effective approach to enhance the charging rates of lithium ion batteries (LIBs) by strategically incorporating carbon nanotube (CNT) conductivity boosters into Li4Ti5O12 (LTO) electrodes. Multi-layer architectures comprising CNT-rich and CNT-free LTO electrode layers were manufactured using a layer-by-layer spray coating method to promote charge transfer kinetics of high mass loading electrodes. The best performing multi-layer was paired with a spray-coated LiFePO4 (LFP) positive electrode, resulting in attractive power performance that outperformed conventional LTO || LFP combinations.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2024)
Article
Materials Science, Multidisciplinary
Ching Kiat Yong, Elspeth M. Keating, Darren J. Hughes, Thomas Connolley, Geoff West, Chow Cher Wong, Gregory J. Gibbons
Summary: For the first time, the through-thickness residual strain profile of an additively-manufactured IN718 sample due to laser shock peening (LSP) is demonstrated. This provides valuable insights into the potential of using LSP to extend the fatigue life of additively-manufactured samples. The peening process led to significant beneficial compressive in-plane residual strains, extending to a depth of 1.0mm.
Article
Chemistry, Physical
Sang Ho Lee, Patrick S. Grant
Summary: Additive-free electrode architectures were fabricated using a layer-by-layer spray coating approach to enhance the capacity and reduce the cost of lithium-ion battery cells. By reducing the binder fraction and conductivity enhancers, all-additive-free full cell LIB configurations with high energy density and power performance were achieved.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Insung Han, Shikang Feng, Fabian Wilde, Patrick S. Grant, Enzo Liotti
Summary: Hot tears during alloy solidification can have catastrophic effects on cast tensile properties. While there are correlations between casting conditions and hot tear sensitivity, the influence of microstructure on tearing has not been fully understood. In this study, in situ X-ray radiography is used to quantify the formation and growth of hot tears in Al-5Cu and Al-5Cu-1Fe alloys, and an automated hot tear detection algorithm is developed to analyze the role of IMC particles in hot tear behavior.
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.
