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)
Article
Chemistry, Physical
Thomas Rieger, Jean-Marc Joubert, Regis Poulain, Xavier Sauvage, Elie Paccou, Loic Perriere, Ivan Guillot, Guy Dirras, Guillaume Laplanche, Mathilde Laurent-Brocq, Jean-Philippe Couzinie
Summary: This study investigates the coarsening kinetics of four complex concentrated alloys in the Al-Ti-Cr-Fe-Co-Ni system. The results show that the chemical compositions of the alloys have a significant impact on Ostwald ripening. By using atom probe tomography and thermo-kinetic modeling, the key parameters affecting ripening are identified and the corrected activation energies are in better agreement with diffusion data.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Bharat Gwalani, Shivakant Shukla, Donovan Leonard, Jonathan D. Poplawsky, Dean T. Pierce, Libor Kovarik, Govindarajan Muralidharan, Arun Devaraj
Summary: The study investigates the phase stability and microstructural evolution of Ni-Fe-Cr-Al-Ti alloys, and discusses the influence of heat treatment on the alloy's microstructure. Long-term aging was found to result in the coarsening and shape change of gamma' precipitates, as well as the formation of eta phase precipitates.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Abhishek Sharma, Chandan Mondal, Kamanio Chattopadhyay, Dipankar Banerjee, Surendra Kumar Makineni
Summary: This study provides a detailed analysis of the deformation micromechanisms involved in the compressive creep of a directionally solidified Cobalt-base superalloy at various stresses and temperatures. The results show different deformation modes under different stress levels, leading to variations in the macroscopic creep behavior.
Article
Materials Science, Multidisciplinary
A. M. S. Costa, J. P. Oliveira, J. D. Escobar, C. A. F. Salvador, M. J. Monteiro, J. D. Poplawsky, C. A. Nunes, A. J. Ramirez, A. P. Tschiptschin
Summary: This study investigates the microstructure and elemental partitioning in a Co-40Ni-10Al-7.5W-10Cr-3Nb-0.06B-0.6C (at.%) superalloy (referred to as 3Nb) after a two-step heat treatment. It was found that Nb preferentially partitioned to the gamma'-phase, while elements like Ni, Cr, and W were responsible for the formation of the mu-phase.
Article
Nanoscience & Nanotechnology
Aparna Saksena, Dorota Kubacka, Baptiste Gault, Erdmann Spiecker, Paraskevas Kontis
Summary: This study uses the gamma-gamma' microstructure as a nanoscale diffusion couple to investigate the diffusion behavior of alloying elements in nickel-based superalloys under different widths of gamma channels, revealing a width-dependent compositional evolution that may impact the microstructural and compositional predictions of service life for nickel-based superalloys.
SCRIPTA MATERIALIA
(2022)
Article
Nanoscience & Nanotechnology
Colin A. Stewart, Richard W. Fonda, Keith E. Knipling
Summary: An ICME approach was utilized to design a fully Austenitic, Mn-stabilized steel strengthened by nano-scale precipitate phases. Experimental verification confirmed that significant strengthening can be achieved by adding Cu together with Ni+Al, forming FCC-Cu and beta-NiAl nano-precipitates.
SCRIPTA MATERIALIA
(2021)
Article
Materials Science, Multidisciplinary
Jiachen Zhang, Lin Liu, Taiwen Huang, Jia Chen, Kaili Cao, Xinxin Liu, Jun Zhang, Hengzhi Fu
Summary: The morphological evolution and coarsening kinetics of gamma' precipitates in a Re-containing Ni-based single crystal superalloy were investigated during isothermal aging at different temperatures. Different coarsening models were examined to fit between the experimental results and theoretical analysis, revealing the role of Re and Al diffusion in the rate-limiting steps of coarsening. The coarsening mechanism was divided into four regimes based on the experimental data and predictions of models.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Zhe Ma, Yan-Ling Pei, Liang Luo, Lu Qin, Shu-Suo Li, Sheng-Kai Gong
Summary: "The study found that in low-density single crystal alloys with high Mo content, the addition of extra Mo increases the lattice misfit and volume fraction of γ/γ' phases, while also influencing the elemental distribution in γ and γ' phases, especially with Re and Cr. Additionally, after the addition of Mo, Re showed a higher partitioning ratio (k)."
Article
Materials Science, Multidisciplinary
Semanti Mukhopadhyay, Prafull Pandey, Nithin Baler, Krishanu Biswas, Surendra Kumar Makineni, Kamanio Chattopadhyay
Summary: The paper investigates the influence of Ti addition on Ta stabilized gamma/gamma' two-phase Co-based superalloys. It was found that an increase in Ti content reduces the gamma/gamma' lattice misfit and Mo partitioning to the gamma', while improving high-temperature strength. Additionally, aging of the alloys resulted in a morphological transition of the precipitates and a preference for Ti partitioning to the gamma'.
Article
Chemistry, Physical
Jiachen Zhang, Taiwen Huang, Fan Lu, Kaili Cao, Dong Wang, Jian Zhang, Jun Zhang, Haijun Su, Lin Liu
Summary: The addition of 2 wt% Re significantly affected the stability of γ' precipitates in Ni-based single crystal superalloys during long-term aging, enhancing their stability and reducing lattice misfit. Re also decreased the effective diffusion coefficient of the alloy, effectively hindering the matrix-diffusion-controlled coarsening of γ' precipitates.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Cuiping Wang, Chi Zhang, Yichun Wang, Jiajia Han, Weiwei Xu, Xingjun Liu
Summary: This study investigated the effects of various alloying elements on the structural stability, mechanical properties, and high-temperature stability of gamma'-Co3Nb through first-principles calculations. It was found that certain elements, such as Ti, Ta, Hf, Pt, Ir, Zr, and V, significantly improved the stability and mechanical properties of gamma'-Co3Nb, and expanded its stable temperature range, making them potential alloying elements for enhancing high-temperature stability.
Article
Nanoscience & Nanotechnology
Namrata Mazumder, Dipanjan Kumar, Mahander Pratap Singh, Surendra Kumar Makineni, Nilay Krishna Mukhopadhyay, Kamanio Chattopadhyay
Summary: The paper examines the impact of multimodal gamma' distribution on the thermophysical and mechanical properties of CoNi-based superalloys. By varying the Ti composition, different types of gamma' size distributions were obtained, and the study reveals an anomaly in the solvus of primary gamma' as a result of the increase in Ti composition, which influences the microstructure. The research also establishes a direct correlation between the nature of gamma' distribution, its composition, and the yield strength of the alloys at room and high temperatures.
SCRIPTA MATERIALIA
(2023)
Article
Chemistry, Physical
Cheng Ai, Qing Li, Jun Zhang, Haijun Su, Wenchao Yang, Lin Liu, Yi Ru, Heng Zhang, Yuanyuan Song, Yongnan Chen, Shusuo Li, Shengkai Gong
Summary: Substituting Mo for W increases Re content in the γ phase and solid solution strength, while decreasing Re content in the γ' phase with increasing W + Ta content. Partitioning ratios of W and Mo elements are positively correlated with Ta content, while the partitioning ratio of Ta is inversely correlated with Ta/Al ratio in single crystal superalloy.
Article
Materials Science, Multidisciplinary
Jiachen Zhang, Taiwen Huang, Kaili Cao, Jia Chen, Huajing Zong, Dong Wang, Jian Zhang, Jun Zhang, Lin Liu
Summary: The microstructural evolution and γ' precipitate morphology of Re-containing Ni-based single crystal superalloys were significantly affected by the addition of Tantalum. Tantalum improved the microstructural stability and resistance to γ' coalescence in long-term aging. The calculated interfacial energy was used to elucidate the γ' kinetic pathways, with simulation results agreeing with experimental data, showcasing the reasonable nature of the model and parameters used.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Rimma Lapovok, Yaron Amouyal, Yuanshen Qi, Alex Berner, Anna Kosinova, Eugene Lakin, Dmitri A. Molodov, Emil Zolotoyabko
JOURNAL OF MATERIALS SCIENCE
(2020)
Article
Nanoscience & Nanotechnology
Amram Azulay, Marwan Wahabi, Yuriy Natanzon, Yaron Kauffmann, Yaron Amouyal
ACS APPLIED MATERIALS & INTERFACES
(2020)
Article
Optics
Michael Shentcis, Adam K. Budniak, Xihang Shi, Raphael Dahan, Yaniv Kurman, Michael Kalina, Hanan Herzig Sheinfux, Mark Blei, Mark Kamper Svendsen, Yaron Amouyal, Sefaattin Tongay, Kristian Sommer Thygesen, Frank H. L. Koppens, Efrat Lifshitz, F. Javier Garcia de Abajo, Liang Jie Wong, Ido Kaminer
Article
Materials Science, Multidisciplinary
Meir Haim Dahan, Andrei Baranovskiy, Yuriy Natanzon, Yaron Amouyal
Summary: The study investigated the diffusion behavior of Ag in PbTe compounds, revealing that Ag diffused in PbTe through an interstitial mechanism. This information provides practical tools for controlling the nucleation and growth of Ag-rich precipitates, ultimately offering predictive insights into the thermal stability of PbTe-based compounds.
Article
Materials Science, Multidisciplinary
Efrat Shukrun Farrell, Nir Ganonyan, Ido Cooperstein, May Yam Moshkovitz, Yaron Amouyal, David Avnir, Shlomo Magdassi
Summary: Aerogels, the lightest solid material known, are nanoporous solids with low density, widely used in various applications. This study introduces a new comprehensive solution for preparing aerogels photochemically and fabricating them in complex shapes at different scales.
APPLIED MATERIALS TODAY
(2021)
Article
Nanoscience & Nanotechnology
Gil Solomon, Erdong Song, Chhatrasal Gayner, Julio A. Martinez, Yaron Amouyal
Summary: The experiment showed that the electrical conductivity, Seebeck coefficient, and charge carrier mobility of the Bi2Te3 samples increase with the reduction of grain size, while Nd-doping reduces these properties and reverses the dependence of mobility on grain size compared to undoped Bi2Te3.
ACS APPLIED NANO MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Chhatrasal Gayner, Yuriy Natanzon, Yaron Amouyal
Summary: In this study, Al and Ti co-doped ZnO with second and third phases were synthesized to enhance its power factor and unusual behavior was observed. By co-doping and employing a multiphase structure, the thermoelectric figure of merit was significantly increased.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Maurizio Riesner, Rachel Fainblat, Adam K. Budniak, Yaron Amouyal, Efrat Lifshitz, Gerd Bacher
Summary: This study investigates the temperature dependence of Fano resonances observed in photoluminescence from flakes of layered semiconductor antiferromagnet chromium thiophosphate (CrPS4). Two Fano resonances with different temperature dependencies are identified. The continuous background responsible for the resonances is attributed to the d-d transition of the optically active Cr3+ center, while the interfering discrete states are suggested to arise from localized atomic phosphorus.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Adam K. Budniak, Szymon J. Zelewski, Magdalena Birowska, Tomasz Wozniak, Tatyana Bendikov, Yaron Kauffmann, Yaron Amouyal, Robert Kudrawiec, Efrat Lifshitz
Summary: Lamellar structures of transition metal phosphorus trisulfides have strong intralayer bonding and weak van der Waals interactions, leading to unique optical and long-range magnetic properties. This study successfully grew large FePS3 crystals and identified their crystallographic structure and composition using advanced electron microscopy techniques. Temperature-dependent experiments revealed the correlation between optical behavior and magnetic phase transition.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Michal Keret-Klainer, Royi Padan, Yuri Khoptiar, Yaron Kauffmann, Yaron Amouyal
Summary: This study focuses on the effects of heat treatments on the microstructure, thermal and electrical conductivities of Ni50.9Ti29.6Hf19.5 SMA. The results show that heat treatments significantly affect the microstructure and increase the transformation temperature and thermal conductivity of the alloy.
JOURNAL OF MATERIALS SCIENCE
(2022)
Article
Nanoscience & Nanotechnology
Chhatrasal Gayner, Yuriy Natanzon, Yaron Kauffmann, Yaron Amouyal
Summary: This study investigates the correlation between grain size, misorientation, and lattice strain in Bi2Te3 and its effect on its thermoelectric (TE) performance. The results show that the electron mobility increases initially with increasing grain size but decreases at higher grain sizes. It is also found that the lattice strain induced by grain size reduction and point defects plays a crucial role in triggering the topological insulator (TI) contribution to TE transport.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Ceramics
Amram Azulay, Tohar Leibovitz, Yuriy Natanzon, Or Zabari, Yaron Amouyal
Summary: In this study, we investigated the phase stability, microstructure, and thermoelectric transport properties of polycrystalline bulk Ca3-xRxMn2O7 samples. Y-doping was found to reduce the potential energy barrier for electron transport, while La-doping did not induce any phase transformation. La-doping hindered grain growth, whereas Y-doping reduced the activation energy for conduction. Computational predictions and calculations supported these experimental findings, highlighting the correlation between electronic transport and elastic properties in layered perovskites.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Nanoscience & Nanotechnology
Chhatrasal Gayner, Luke T. Menezes, Yuriy Natanzon, Yaron Kauffmann, Holger Kleinke, Yaron Amouyal
Summary: Nanostructuring of thermoelectric materials can improve energy conversion performance, but requires a perfect match between the nanoprecipitates' chemistry and crystal structure and those of the matrix. In this study, we synthesized bulk Bi2Te3 from molecular precursors and characterized its structure and chemistry. The resulting n-type Bi2Te3 with Te nanoprecipitates showed enhanced thermoelectric performance and promising figure of merit values.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Ceramics
Yixuan Shi, Zahra Sepahi, Leilane R. Macario, Cheryl Sturm, Nour Mashmoushi, Yaron Amouyal, Holger Kleinke
Summary: We studied the impact of varying amounts of CaO layers on the thermoelectric properties of the Ruddlesden-Popper series CaO(CaMnO3)(m) with m = 1, 2, 3, infinity. Dense pellets were obtained through extended ball-milling and hot-pressing, with the sample containing the most CaO layers (m = 1) exhibiting the lowest electrical and thermal conductivity and the highest Seebeck coefficient. Ultimately, the perovskite CaMnO3 (m = infinity) without CaO layers showed the best thermoelectric properties.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Materials Science, Multidisciplinary
Robert Oliva, Esther Ritov, Faris Horani, Inigo Etxebarria, Adam K. Budniak, Yaron Amouyal, Efrat Lifshitz, Mael Guennou
Summary: Alloyed MnxZn1-xPS3 samples were grown and studied using Raman spectroscopy and magnetic measurements. The results showed that the alloy retains antiferromagnetism at x = 0.3 and identified the Raman signatures of a magnetic transition. Spin-phonon coupling and lattice-dynamical calculations were used to explain these signatures. Comparisons with other compounds confirmed the occurrence of a second-order Jahn-Teller effect in ZnPS3 and Zn-rich MnxZn1-xPS3.