Article
Materials Science, Ceramics
Man Zhang, Jianhua Liu, Junwen Zhou
Summary: The effect of Eu2O3 doping amount on the densification behavior of MgAl2O4 and its corrosion resistance to aluminum electrolyte was studied. The results showed that Eu2O3 doping contributed to the densification of MgAl2O4, and the sample with 3 wt.% Eu2O3 had the highest relative density and hardness. Additionally, this sample exhibited the best corrosion resistance to aluminum electrolyte.
CERAMICS INTERNATIONAL
(2022)
Article
Engineering, Biomedical
Mehran Ghodrati, Seyed Mahdi Rafiaei, Lobat Tayebi
Summary: In this study, magnesium aluminate spinel (MgAl2O4) nanoparticles were synthesized using a combustion approach and then incorporated into PLA to prepare scaffolds. The crystal structure, microstructure, biodegradability, and thermal characteristics of the materials were investigated using XRD, FESEM, ICP, STA, and compressive strength analyses. The results showed that PLA/6 wt% MgAl2O4 scaffolds exhibited the highest compressive strength. Immersion of the scaffolds in SBF revealed improved biodegradability, while improper particle dispersion occurred at higher MgAl2O4 loadings.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Markus Mader, Richard Prediger, Karl G. Schell, Gabriela Schmidt, Alex Dorn, Sophie Jenne, Sebastian Kluck, Leonhard Hambitzer, Manuel Luitz, Claudia Schwarz, Marcel Milich, Christian Greiner, Bastian E. Rapp, Frederik Kotz-Helmer
Summary: This study develops a thermoplastic nanocomposite that can be shaped into transparent ceramics using polymer injection molding. The process involves several steps to achieve high density, high optical transmission, and high mechanical strength in the transparent ceramics. By making transparent ceramics accessible to high-throughput polymer processing techniques, this research enables fast and cost-efficient manufacturing of macroscopic and microstructured components, opening up a wide range of potential applications.
Article
Materials Science, Ceramics
Somnath Sinhamahapatra, Chandrima Ghosh, Himansu Sekhar Tripathi, Sunanda Mukhopadhyay
Summary: The magnesium aluminate spinel was prepared from constituent oxides through a solid-state sintering process at temperatures ranging from 1550 to 1700 degrees C in a normal air atmosphere. The addition of TiO2 and Yb2O3 improved the densification and mechanical properties of the magnesia-rich spinel, with Yb2O3 showing better performance in room temperature flexural strength.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Ceramics
Ming Shi, Ying Li, Junjie Shi
Summary: A novel method for fabricating periclase and magnesium aluminate spinel refractory from secondary aluminum dross was proposed. The study analyzed the fabrication mechanism and studied the effects of MgO addition and sintering temperature on the properties of refractories. The results showed significant improvement in purity, crystallinity, densification, flexural strength, and impact toughness with increasing sintering temperature and MgO addition.
CERAMICS INTERNATIONAL
(2022)
Article
Materials Science, Ceramics
Aref Basiri, Amir Hossein Nassajpour-Esfahani, Mohammad Reza Haftbaradaran-Esfahani, Amir Alhaji, Ali Shafyei
Summary: This study investigated the granulation process of magnesium aluminate spinel powders using spray freeze drying method. The optimal amount of binder was found to be 3%, and the ideal solid load was determined to be 35 wt%, resulting in granules of 10-50 μm in size. Powder granulation increased density by approximately 20% and improved the in-line transmission for the IR range by over 15%.
CERAMICS INTERNATIONAL
(2022)
Article
Materials Science, Ceramics
Ali Talimian, H. F. El-Maghraby, Monika Michalkova, Dusan Galusek
Summary: Adding 0.3 wt% lithium hydroxide can promote densification and limit grain growth of MgAl2O4, while also affecting the activation energy of sintering. The formation and disappearance of secondary phases were observed, with magnesium oxide and lithium aluminum oxide produced at certain temperatures.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2021)
Article
Chemistry, Physical
Hu Tang, Zhenggang Jia, Bing Li, Huazhong Chen, Wenjie Yuan
Summary: In order to achieve the goal of dual-carbon, attention has been paid to induction furnaces with high efficiency and energy-saving advantages in the foundry and metallurgy industries. The service life and safety of induction furnaces strongly depend on the lining, which can be eroded and have poor slag resistance due to expansion and forward sintering. This study focused on the properties of alumina-magnesia-based dry ramming mixes and replaced calcined magnesia particles with a novel multi-component material, calcium magnesium aluminate (CaO-MgO-Al2O3, CMA), with a size of 200 mesh. The effects of CMA on the bulk density, apparent porosity, strength, and slag corrosion resistance of the dry ramming mixes were evaluated. The results showed that the addition of CMA reduced the slag penetration index and permanent linear change in the dry ramming mixes.
Article
Materials Science, Ceramics
Wenyu Zan, Beiyue Ma, Yutong Cao, Jialong Tian, Zhangyan Zhou, Lulu Wang, Zhouhua Jiang
Summary: In this study, MgAl2O4 spinel materials were synthesized using a single-step reaction sintering method. The effects of (MgO + Al2O3) content, molding pressure, and YSZ additive on the properties of the material were investigated. The results showed that increasing (MgO + Al2O3) content and molding pressure favored the formation of the second MgAl2O4 spinel but also increased the apparent porosity. YSZ addition induced defects and improved the sintering and mechanical properties. The optimal material was obtained with the addition of 1 wt% YSZ, 80 wt% of (MgO + Al2O3), and molding at 200 MPa, followed by sintering at 1600 degrees C for 2 h. The material exhibited high strength retention and comprehensive performance after thermal shock.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Worachita Wongtawee, Pongsaton Amornpitoksuk, Chamnan Randorn, Tanattha Rattana, Sumetha Suwanboon
Summary: A nanocomposite photocatalyst consisting of MgAl2O4 spinel and WO3 powders was synthesized through grinding. Characterization using various techniques revealed the presence of WO3 and MgAl2O4 in the nanocomposite. The nanocomposite showed a shift in absorption edge and a decrease in optical band gap energy compared to pure WO3. The nanocomposite also exhibited higher photocatalytic degradation efficiency for methylene blue, with the most complete degradation achieved using a 20%WO3/MgAl2O4 nanocomposite.
INORGANIC CHEMISTRY COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Biswajit Baruah, Ritwik Sarkar
Summary: This study investigated the effect of samarium oxide (Sm2O3) as an additive on the properties of stoichiometric magnesium aluminate spinel using different raw material sources. Six spinel batches were prepared with commercially available alumina and magnesia, and the effect of Sm2O3 addition on the properties of the spinel compositions was studied. The results showed that 1% of Sm2O3 addition led to improved densification and strength of the spinel compositions.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2023)
Article
Engineering, Chemical
Inna G. Antropova, Aryuna D. Budaeva, Darya P. Khomoksonova, Seseg Yu. Batueva, Pavel A. Gulyashinov
Summary: This article focuses on the deep processing of synnyrite to produce valuable agricultural and technical products. The research shows the promise of using magnesite instead of limestone in the thermochemical activation process, which reduces costs and generates an additional useful product. The article also presents a new method for processing alum obtained from synnyrite to produce potassium magnesium sulfate and magnesium aluminate spinel.
MINERALS ENGINEERING
(2022)
Article
Chemistry, Physical
Xiuyi Liu, Zhe Chen, Wen Yan, Jingran Wang, Sanbao Ma, Guangqiang Li
Summary: Lightweight design and preparation of refractories can contribute to energy saving and emissions reduction in high temperature furnaces. Two lightweight periclase-magnesium aluminate spinel refractories were prepared using microporous aggregates and compared to commercial dense refractories. The results showed that the lightweight specimens had increased strength, reduced thermal conductivity, and improved microstructure due to the microstructure of the microporous aggregates.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Ceramics
L. Zarazua-Villalobos, G. Fantozzi, G. Bonnefont, L. Tellez-Jurado, H. Balmori-Ramirez
Summary: Transparent magnesium aluminate spinel was obtained through one-step spark plasma reaction-sintering (SPRS) using different precursor powders. The HT450 and HT850 powders showed better sinterability and transparency, likely due to the higher reactivity of their precursor particles.
CERAMICS INTERNATIONAL
(2022)
Article
Materials Science, Ceramics
Anu Sharma, Manu Krishnan, Gurudatta Ganganahalli, Seema Saraswathy, Papiya Biswas, Roy Johnson, Kurian Mathew Abraham, Satish R. Iyer
Summary: The magnesium aluminate-based polyphasic composite scaffold demonstrated physical and biological characteristics essential for in vitro craniofacial bone tissue engineering, including good compressive strength, porosity, cell viability, and mineralization.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Physical
Siva P. Padi, Lee Shelly, Eswaravara P. Komarala, Danielle Schweke, Shmuel Hayun, Brian A. Rosen
CATALYSIS COMMUNICATIONS
(2020)
Article
Materials Science, Ceramics
Yuval Mordekovitz, Lee Shelly, Brian A. Rosen, Shmuel Hayun
Summary: The study focused on the effects of titanium doping and co-doping on CeO2 materials in interaction with environmental gases, showing changes in water vapor and CO2 adsorption quantities and heats. Addition of titanium improved the RWGS catalytic performance at certain levels.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Engineering, Industrial
Itzhak Edry, Arthur Shoihet, Shmuel Hayun
Summary: The study investigated the effects of PMO treatment parameters on the structure of solidified aluminum, finding that increasing electric current intensity had a greater impact on grain size than increasing pulse frequency. However, increasing current intensity may also limit refinement efficiency. Simulation calculations showed that solidification decreases the driving force for grain refinement, which should be considered in designing an efficient electrical system setup for grain refinement in pure aluminum.
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Yael Templeman, Malki Pinkas, Eli Brosh, Einat Strumza, Shmuel Hayun, Louisa Meshi
Summary: This study investigates the a-a' phase separation in 14%Cr oxide dispersion strengthened steel during prolonged heat treatments at 400 and 450 degrees C. It was found that a' precipitates after 5,000 hrs at 400 degrees C, while at 450 degrees C precipitation is detected only after 10,000 hrs. Despite this, the amount of a' after 10,000 hrs at 450 degrees C was larger. The results suggest that in 14%Cr ODS steel, the separation occurs through nucleation and growth mechanism rather than spinodal decomposition.
Article
Materials Science, Multidisciplinary
Mahdi Halabi, Amit Kohn, Shmuel Hayun
Summary: The study focuses on the formation of space charge regions in nanometer-scale crystals of magnesium-aluminate-spinel with an excess of Al2O3. It investigates the types, distribution, and formation energies of charged point defects, revealing V'(Al) and V ''(Mg) cation vacancies as the majority species at the particle core, while Al-Mg defects are richer near the crystal surface.
Editorial Material
Chemistry, Physical
Sergey V. Ushakov, Shmuel Hayun
Article
Chemistry, Physical
Yair Bochlin, Lior Ezuz, Yanir Kadosh, Daniel Benjamin, Yuval Mordekovitz, Shmuel Hayun, Eli Korin, Armand Bettelheim
Summary: A unique three-dimensional graphene-based structure, covalent graphene framework (CGF), was prepared for electrochemical reduction of carbon dioxide, showing enhanced performance for methane production. The porous structure of CGF with free amine functional groups promotes strong adsorption of CO2, highlighting the importance of catalyst morphology and chemical composition in designing efficient catalytic systems for energy conversion.
ACS APPLIED ENERGY MATERIALS
(2021)
Article
Chemistry, Physical
Aharon Farkash, Brigit Mittelman, Shmuel Hayun, Elad Priel
Summary: The impact of weak particle-matrix interfaces in aluminum matrix composites on effective elastic properties was studied using micromechanical finite-element analysis. It was found that a 2D unit cell representation is accurate only for strong particle-matrix bonds and underestimates the effective properties for weak interfaces. Real microstructure computations showed different effective elastic properties under tension and compression for weak interfaces, attributed to local stress and strain fields and contact mechanics between particles and the matrix. Preliminary measurements supported trends observed in computational analysis.
Article
Chemistry, Multidisciplinary
Bar Koren, Ofir Friedman, Nitzan Maman, Shmuel Hayun, Vladimir Ezersky, Yuval Golan
Summary: Thin films of CuSe were deposited on GaAs substrate. XRD analysis showed a Klockmannite phase, while electron diffraction in the TEM surprisingly indicated a beta-Cu2-xSe phase, possibly due to selenium loss during specimen preparation causing phase transition. Control of film phase can be achieved by adjusting reactant composition.
Article
Chemistry, Physical
Adi Azoulay, Alberto Garcia Baldovi, Josep Albero, Noa Azaria, Jonathan Tzadikov, Ayelet Tashakory, Neeta Karjule, Shmuel Hayun, Hermenegildo Garcia, Menny Shalom
Summary: Catalysts consisting of Cu and Fe nanoparticles deposited on lightweight carbon-phosphorous-nitrogen (CPN) materials show good performance in CO2 hydrogenation to methanol at 250 degrees C and 20 bar. The catalysts exhibit high methanol production yield, good selectivity, negligible CO formation, and stability for 12 hours.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Materials Science, Ceramics
Jonathan Mottye, Barak Ratzker, Sergey Kalabukhov, Bar Favelukis, Shmuel Hayun, Nachum Frage
Summary: The effect of Mn-doping on the sintering behavior, optical properties, microstructure, and mechanical properties of alumina was investigated in this study. It was found that the addition of 0.5 at.% Mn significantly reduced densification rate and grain growth during high-pressure spark plasma sintering (HPSPS). The major effect was attributed to the formation of MnAl2O4 nano inclusions located at grain boundary triple points. The Mn-doped alumina exhibited high transparency and a light-brown tint, with absorption between approximately 410 and 580 nm and a cutoff at 300 nm. The addition of Mn decreased the Young's modulus, increased the fracture toughness, and did not affect the hardness of alumina. Therefore, Mn doping enables control of the densification process and microstructure development of transparent alumina, and it can be used to tailor the optical and mechanical properties for specific applications.
CERAMICS INTERNATIONAL
(2023)
Article
Multidisciplinary Sciences
Adi Lavi, Avia Ohayon-Lavi, Yelena Leibovitch, Shmuel Hayun, Efrat Ruse, Oren Regev
Summary: Renewable energy technologies rely on efficient thermal energy storage devices, which often use molten salts. However, the low thermal conductivity of these salts limits their storage kinetics. This study explores the use of partially exfoliated graphite to form graphene nanoplatelets in a molten salt matrix to enhance thermal conductivity. The resulting hybrid composite material shows a significant improvement in thermal conductivity compared to the pristine salt.
Article
Multidisciplinary Sciences
Adi Lavi, Avia Ohayon-Lavi, Yelena Leibovitch, Shmuel Hayun, Efrat Ruse, Oren Regev
Summary: This study explores the partial exfoliation of graphite to graphene nanoplatelets (GnP) in a molten salt matrix to enhance thermal conductivity and the efficiency of thermal energy storage devices.
Article
Engineering, Manufacturing
Dor Braun, Yaron Itay Ganor, Shmuel Samuha, Gilad Mordechai Guttmann, Michael Chonin, Nachum Frage, Shmuel Hayun, Eitan Tiferet
Summary: This study examines the effects of different process parameters on the properties of Ti-6Al-4V alloy in electron beam melting processes. Through experimentation and testing, it is found that specific combinations of parameters can yield high density parts with fine microstructure. The proposed design of experiments method has the potential to improve existing results and develop manufacturing parameters for new materials.
JOURNAL OF MANUFACTURING AND MATERIALS PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
M. Aizenshtein, E. Strumza, E. Brosh, S. Hayun
Summary: The study investigated the microstructure, composition, precipitation kinetics, and thermodynamic calculation of the equilibrium state of the Al0.5CoCrFeNi alloy, revealing temperature-dependent morphology of the B2 phase. The activation energy for B2 phase growth was found to be lower than that of the AlCoCrFeNi alloy, attributed to different lattice distortion parameters. The morphology transformation of the B2 phase is suggested to be caused by increased density of dislocations at the B2/A1 interface with temperature increase.
MATERIALS CHARACTERIZATION
(2021)