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
Qingyuan Qin, Zhao Zhang, Lin Yang, Jinfu Li
Summary: This study establishes a theoretical criterion based on the classical nucleation theory to predict non-reciprocal nucleation using Ag-Cu alloys as examples. It is found that in hypoeutectic alloys, the beta-Cu phase acts as a more effective nucleation substrate for the alpha-Ag phase, while in hypereutectic alloys, the opposite is observed. This non-reciprocal nucleation phenomenon is reflected in the solidification process of the alloys.
METALS AND MATERIALS INTERNATIONAL
(2023)
Article
Materials Science, Multidisciplinary
Bernhard Trink, Irmgard Weissensteiner, Peter J. Uggowitzer, Katharina Strobel, Anna Hofer-Roblyek, Stefan Pogatscher
Summary: This study introduces new alloys that combine the age-hardening capability of Al-Mg-Si alloys with the microstructure-controlling effect on processing of primary Fe-rich intermetallic phases used in foil stock. Processing and microstructure-property relations in new crossover aluminum alloys derived from 6xxx and 8xxx foil stock alloys are shown. The study demonstrates the attractive combinations of strength and ductility achieved in these new alloys.
Article
Engineering, Electrical & Electronic
Xi Wang, Liang Zhang, Chen Chen, Xiao Lu, Wei-min Long
Summary: The growth behavior of interfacial intermetallic compounds (IMC) in Cu/Sn58Bi/Cu and Cu/Sn58Bi-0.05AlN/Cu solder joints under ultrasound-assisted soldering processes was investigated. The effects of ultrasonic soldering and AlN nanoparticles on the shear strength of the solder joints were studied. Ultrasonic vibrations can enhance the mechanical properties of the solder joint by increasing nucleation mass and producing uniform and finer grains, while AlN nanoparticles inhibit the diffusion of Cu elements and reduce the growth rate of the interface IMC, leading to increased shear properties of the solder joint.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2023)
Article
Materials Science, Multidisciplinary
Zhipeng Yuan, Yiyou Tu, Ting Yuan, Yaohua Huang, Yunhe Zhang
Summary: The local electrochemical measurements and corrosion mechanisms of multi-layered aluminium sheets after brazing were determined using mechanical polishing and work function calculations based on density functional theory. It was found that Si and α-Al(Fe,Mn)Si particles in the sheets promoted cathodic reactions and could lead to localized dissolution of the Al matrix. Additionally, the presence of the sacrificial AA7072 layer reduced copper diffusion and improved corrosion protection due to its large potential difference with the core material.
JOURNAL OF MATERIALS SCIENCE
(2021)
Article
Chemistry, Physical
Blaz Leskovar, Saso Sturin, Kemal Delijic, Julian Ledieu, Matejka Podlogar, Sandra Drev, Iztok Naglic, Bostjan Markoli
Summary: This study confirms that crystalline TiB2 particles can act as a potent site for the heterogeneous nucleation of the metastable icosahedral quasicrystalline phase (IQC) formed in cast Al-Mn-Si-Cu-Mg alloys. The results show that the primary IQC phase nucleates on facets of TiB2 particles and adopts different orientation relationships with the crystalline TiB2. Microstructural analyses reveal that inoculation has a noticeable influence on the size and distribution of the primary IQC phase, which subsequently affects the compressive properties of the alloys. These alloys have great potential for lightweight applications, especially in the automotive and aerospace industries.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Feng Qian, Jinyue Li, Dongdong Zhao, Shenbao Jin, Eva A. Mortsell, Yanjun Li
Summary: This work shows that the addition of Cd can enhance the precipitation process in 2xxx and 6xxx alloys, as well as the dispersoid precipitation process in 3xxx alloys, but has minimal effect on the precipitation in 7xxx alloys. Experimental and theoretical methods are used to investigate the nucleation and precipitation process in Cd-containing Al alloys. The enhanced precipitation in different alloys is attributed to different mechanisms, such as heterogeneous nucleation and increased number density of co-clusters.
MATERIALS SCIENCE AND TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Tinku Kumar, Degala Venkata Kiran, Navneet Arora, Srihari Chitral
Summary: The study demonstrates that the use of arc oscillations in the GTAW process can enhance the mechanical properties of Steel/Aluminum lap joints by manipulating the heat energy density on the base metal. Results show a decrease in heat energy density with arc oscillations, leading to improvements in aesthetics, microhardness, and failure strength of the joints.
Article
Acoustics
Nagasivamuni Balasubramani, Jeffrey Venezuela, Nan Yang, Gui Wang, David StJohn, Matthew Dargusch
Summary: The ultrasonic processing of liquid/solidifying melts can result in a refined grain structure and finer intermetallic phases. This process has been widely studied in Al and Mg-based alloys due to its versatility and scalability. The refinement is achieved through cavitation-induced fragmentation mechanisms, and the efficiency of conventional grain refinement can be improved by adding potent particles through master alloys. However, the understanding of the refinement mechanisms is still debated and affected by various solidification variables and casting conditions.
ULTRASONICS SONOCHEMISTRY
(2022)
Article
Engineering, Manufacturing
Junjie Zhao, Chuan Song Wu, Hao Su
Summary: The study found that the thickness of IMCs on the transverse cross-section of the weld first increases and then decreases as the depth distance from the top surface of the weld gets larger, reaching the maximum value at a depth of about 1 mm. On the horizontal plane at the upper part of the weld, the thickness of IMCs increases first and then decreases as the distance gets farther from the center of the exit hole, and reaches a stable stage outside the range covered by the shoulder. The application of ultrasonic vibration can reduce the thickness of IMCs in the whole weld and shift the peak value of IMCs thickness to a location nearer the exit hole on horizontal planes at both upper and lower parts of the weld.
JOURNAL OF MANUFACTURING PROCESSES
(2021)
Article
Acoustics
S. S. Ao, M. P. Cheng, W. Zhang, J. P. Oliveira, S. M. Manladan, Z. Zeng, Z. Luo
Summary: The study found that increasing ultrasonic welding energy input intensified surface oxidation, resulting in voids or unbonded zones at low energy inputs and intimate contact at higher energy inputs. Furthermore, an increase in energy input to 750 J led to the formation of two interfaces at the weld interface, and the lap-shear load of the joints first increased to a maximum value before decreasing with further welding energy input.
Article
Engineering, Environmental
Ping- Chou, Deoukchen Ghim, Prashant Gupta, Srikanth Singamaneni, Byeongdu Lee, Young-Shin Jun
Summary: Due to its thermodynamics and kinetics properties, heterogeneoussolid nucleation on membranes leads to early-stage mineral scaling. In this study, we used in situ grazing incidence small angle X-ray scattering and ex situ atomic force microscopy to investigate the heterogeneous nucleation of iron (hydr)oxide on surface functional groups commonly used in membranes, including hydroxyl (OH), carboxyl (COOH), and fluoro (F) groups. We observed that the hydrophobic F-modified surface significantly reduced both heterogeneously and homogeneously formed iron (hydr)oxide nucleation compared to the hydrophilic OH- and COOH-surfaces. The kinetic and thermodynamic information obtained provides insights into the early-stage scaling of iron (hydr)oxide nanoparticles in membrane processes.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
J. Ren, M. L. Huang
Summary: The ultrasonic-assisted soldering process has been proven to enhance the interfacial microstructural evolution and shear strength of Al/Sn-9.77Zn-11.36Bi-1.46Ag/Cu solder joints. Increasing the ultrasonic soldering temperature, time, and power results in a higher shear strength of the solder joints.
SCIENCE AND TECHNOLOGY OF WELDING AND JOINING
(2021)
Article
Materials Science, Multidisciplinary
Ahmed Teyeb, Joao Silva, Jamil Kanfoud, Phil Carr, Tat-Hean Gan, Wamadeva Balachandran
Summary: This study investigated the use of ultrasonic vibrations to improve the microstructure and mechanical properties of aluminium alloy during welding. The results showed that by irradiating the welds with optimum ultrasonic variable values, the tensile and weld yield strengths of laser welds in the aluminium plates increased by 26%.
Article
Thermodynamics
Jingru Liu, Hongwei Liang
Summary: Nano-zinc oxide is an efficient beta-nucleating agent for isotactic polypropylene, promoting the formation of beta-crystal with certain concentration; The efficiency of nano-ZnO as a beta-nucleating agent is dependent on its concentration and dispersibility.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Materials Science, Multidisciplinary
Alexander Pervikov, Andrey Filippov, Yuri Mironov, Mark Kalashnikov, Maksim Krinitcyn, Dmitry Eskin, Marat Lerner, Sergei Tarasov
Summary: Nanostructured W-31wt.%Cu composite was successfully produced via magnetic pulse compaction, featuring recrystallized copper grains and unreacted spherical tungsten particles with high density and mechanical strength. The composite showed reduced wear in high temperature tribological tests, attributed to the generation of copper tungstate CuWO4 on the worn surfaces.
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
(2022)
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
Chemistry, Physical
Anastasia Tyurnina, Justin A. Morton, Amanpreet Kaur, Jiawei Mi, Nicole Grobert, Kyriakos Porfyrakis, Iakovos Tzanakis, Dmitry G. Eskin
Summary: In this study, a new dual frequency ultrasound-aided liquid phase exfoliation (ULPE) approach was used to produce high-quality few-layer graphene (FLG) solutions in eco-friendly media. The correlation between the final graphene flakes structure and the properties of each individual solution was confirmed using advanced characterization techniques. Ethanol and surfactants were found to play a crucial role in regulating the cavitation power and intensity of the ultrasonic field, as well as the cavitation effectiveness in different solutions.
Article
Chemistry, Physical
Justin A. Morton, Amanpreet Kaur, Mohammad Khavari, Anastasia V. Tyurnina, Abhinav Priyadarshi, Dmitry G. Eskin, Jiawei Mi, Kyriakos Porfyrakis, Paul Prentice, Iakovos Tzanakis
Summary: Ultrasonic assisted liquid phase exfoliation (ULPE) is a promising method for large scale production of 2D materials. In this study, different solvents were examined for their bubble dynamics and acoustic emissions to determine a suitable eco-friendly solvent for ULPE of graphite. The optimal solvent, a mixture of deionised water and ethanol, produced high quality few layer graphene with a high yield, stability, and potential for commercial manufacturing.
Article
Mechanics
Justin A. Morton, Mohammad Khavari, Abhinav Priyadarshi, Amanpreet Kaur, Nicole Grobert, Jiawei Mi, Kyriakos Porfyrakis, Paul Prentice, Dmitry G. Eskin, Iakovos Tzanakis
Summary: Research has found that using a dual frequency transducer system can enhance cavitation activity and expand the cavitation cloud, resulting in more shock waves. This is crucial for optimizing existing cavitation-based processing technologies.
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
Chemistry, Physical
Abhinav Priyadarshi, Tungky Subroto, Jiri Nohava, Sedmak Pavel, Marcello Conte, Koulis Pericleous, Dmitry Eskin, Iakovos Tzanakis
Summary: This study performed nano-indentation experiments to measure the mechanical properties of single and polycrystalline Al3Zr specimens from ambient to elevated temperatures. The results showed that the hardness and elastic modulus of Al3Zr intermetallics depended on the crystal structure/orientation, with polycrystalline samples exhibiting higher elastic modulus at room temperature. Additionally, high-temperature measurements revealed that intermetallics had high creep resistance at low and intermediate temperatures, but exhibited significant plastic deformation and creep close to the melting point of pure aluminium.
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)
Editorial Material
Acoustics
Dmitry Eskin, Sergey Komarov, Iakovos Tzanakis
ULTRASONICS SONOCHEMISTRY
(2023)
Article
Acoustics
Mohammad Khavari, Abhinav Priyadarshi, Justin Morton, Kyriakos Porfyrakis, Koulis Pericleous, Dmitry Eskin, Iakovos Tzanakis
Summary: This paper investigates the effects of different liquid physical properties on shock wave characteristics. The experiments were conducted using ethanol, glycerol, and a 1:1 ethanol-water solution as substitutes for water. The results show that ethanol and glycerol barely exhibited a shock wave pressure peak, particularly at low input powers, while the 1:1 ethanol-water solution and water consistently showed the presence of a shock wave pressure peak.
ULTRASONICS SONOCHEMISTRY
(2023)
Article
Materials Science, Multidisciplinary
S. Chankitmunkong, D. G. Eskin, C. Limmaneevichitr, P. Pandee
Summary: The effects of ultrasonic treatment on in-situ ZrB2 particle-reinforced AA4032-based composites were investigated. The composites were synthesized by an in-situ melt reaction from the Al-K2ZrF6-KBF4 system. The addition of in-situ submicron ZrB2 particles resulted in grain refinement, increased hardness, and tensile properties. Ultrasonic treatment effectively improved the uniformity of ZrB2 distribution, enhancing the structure and mechanical properties of the composites. Mechanisms of the ultrasonic treatment in improving particle distribution and mechanical properties were discussed.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
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
Materials Science, Multidisciplinary
Suwaree Chankitmunkong, Feng Wang, Chaowalit Limmaneevichitr, Dmitry G. Eskin
Summary: Ternary Al-Ce-Ni alloys have potential in various applications and can replace traditional aluminum alloys in high-temperature environments. The addition of Zr and Zr + Sc, along with ultrasonic melt processing, improves the microstructure and mechanical properties of a hypoeutectic Al4Ce2Ni alloy. The strength is further enhanced by the presence of hardening nanoprecipitates and the use of ultrasonic melt processing.
ADVANCED ENGINEERING MATERIALS
(2023)
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
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.
