Article
Materials Science, Multidisciplinary
Zijuan Xu, Zhongtao Li, Yang Tong, Weidong Zhang, Zhenggang Wu
Summary: The study systematically investigated a Cu-rich non-equiatomic HEA, revealing changes in alloy behavior during thermal cycles and thermomechanical processing, including continuous melting and discontinuous solidification of Cu-rich and CoCrFeNi-rich phases. The alloy softened and became more ductile after annealing at different temperatures, with varying effects on mechanical properties. The observation of yield-drop phenomena at certain annealing temperatures suggests further research is needed to understand the locking of pre-existing dislocations by unknown atmospheres.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Physical
Vikas Shivam, Shubhada Kar, Gaurav K. Bansal, Avanish K. Chandan, Biraj K. Sahoo, G. K. Mandal, N. K. Mukhopadhyay, V. C. Srivastava
Summary: A cost-effective iron-rich non-equiatomic Fe50Mn20Al15Ni10Co5 medium entropy alloy (MEA) was synthesized by vacuum induction melting. The as-cast alloy exhibits a multiphase microstructure and has shown high compressive yield strength and ultimate strength, as well as good ductility. These results provide direction for designing and developing economically viable alloys at an industrial scale.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
You Sub Kim, Hobyung Chae, E-Wen Huang, Jayant Jain, Stefanus Harjo, Takuro Kawasaki, Sun Ig Hong, Soo Yeol Lee
Summary: In this study, a non-equiatomic high-entropy alloy with a stable solid solution and high stacking fault energy was successfully manufactured. The alloy exhibited a good combination of strength and ductility, which can be attributed to the active motion of dislocations and lattice distortion.
Article
Nanoscience & Nanotechnology
Z. Y. Jia, S. Z. Zhang, J. T. Huo, C. J. Zhang, L. W. Zheng, F. T. Kong, H. Li
Summary: In this study, a non-equiatomic Ni46Co24Fe24Al3Ti3 medium entropy alloy was prepared by vacuum suspension melting. After thermo-mechanical processing, the alloy exhibited excellent mechanical properties, which can be attributed to its unique microstructure.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Nanoscience & Nanotechnology
Chenliang Chu, Liangyan Hao, Weiping Chen, Wei Xiong, Jiacheng Niu, Zhiqiang Fu
Summary: The phase transformation, microstructure, and mechanical behavior of a non-equiatomic Ti10Fe30Co30Ni30 medium entropy alloy were systematically studied. The study found that the alloy's composition and microstructure changed under different states, which influenced its mechanical properties.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
M. Rezayat, F. Najib
Summary: Through a thermal-mechanical process, the average grain size of Co35Ni34Cr24Mo7 medium entropy alloy was reduced to 2 μm, resulting in a 50% improvement in hardness. The kinetics of recrystallization and grain growth were investigated through annealing experiments. It was found that the Austin-Ricket approach for recrystallization modeling was more accurate, and the presence of annealing twins affected the relation between grain size and hardness.
METALS AND MATERIALS INTERNATIONAL
(2023)
Article
Nanoscience & Nanotechnology
Hanqing Xu, Ziyang Li, Wei Zhou, Lianhua Ma, Mengdi Zhang, Gong Li
Summary: By adjusting the elements Al and Ti through the non-equiatomic design concept, the yield strength of high-entropy alloys can be improved. High gigapascal compressive yield strength and relatively good ductility were achieved in the FCC + L1(2)+BCC structured high-entropy alloys system. The addition of Al and Ti simultaneously showed superior micromechanical behaviors and contributed to the strength increment through multiple strengthening mechanisms.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Chemistry, Physical
Hyeonseok Kwon, Peyman Asghari-Rad, Jeong Min Park, Praveen Sathiyamoorthi, Jae Wung Bae, Jongun Moon, Alireza Zargaran, Yeon Taek Choi, Sujung Son, Hyoung Seop Kim
Summary: A strategy to improve the tensile properties of Co17.5Cr12.5Fe55Ni10Mo5 medium-entropy alloy through high-pressure torsion and subsequent annealing was presented. The combination of grain refinement and precipitation contributed to excellent strength, while post-HPT annealing provided substantial ductility, resulting in a yield strength of 1 GPa with over 15% uniform elongation.
Article
Materials Science, Multidisciplinary
Jian Wu, Xiaoyan Liu, Heguo Zhu
Summary: Investigated the effects of aluminum doping on the mechanical and wear properties of medium-entropy alloy AlxNi0.6CoFe1.4. Found that aluminum addition can enhance the mechanical properties and wear resistance, with the Al0.2 alloy exhibiting the best overall performance.
MATERIALS CHARACTERIZATION
(2023)
Article
Nanoscience & Nanotechnology
Hao Peng, Yixin An, Bingfeng Wang
Summary: The equiatomic TiZrV medium-entropy alloy with diphasic heterostructure shows great potential for structural applications, and its mechanical properties can be improved through precipitation strengthening and high-density dislocation strengthening.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Nanoscience & Nanotechnology
Shuzhi Zhang, Zhiyuan Jia, Guangxu Zhao, Jing Zhang, Jianchao Han, Changjiang Zhang, Fantao Kong
Summary: High entropy alloys are ideal structural materials with excellent mechanical properties. A novel L12 precipitation strengthened medium entropy alloy is designed, which exhibits a yield strength of 1.09 GPa, an ultimate tensile strength of 1.5 GPa, and nearly 20% elongation at room temperature. However, the fully recrystallized as-aged alloy has poor plasticity at high temperature, while the non-recrystallized alloy directly aged after rolling shows excellent high temperature mechanical properties.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Chemistry, Physical
Wenjie Lu, Xian Luo, Yanqing Yang, Bin Huang, Pengtao Li
Summary: The novel non-equiatomic Ni-Cr-Co-Ti medium-entropy alloy strengthened by heterogeneous precipitates exhibits exceptional strength-ductility synergy properties, high yield strength and ultimate tensile strength, as well as excellent ductility. Further analysis reveals the effective precipitation strengthening enhancement, stacking-faults activation, and deformation nanotwins induction, contributing to the alloy's high work-hardening capacity and ductility. This work provides valuable insights into precipitation behaviors and strengthening mechanisms in high/medium-entropy alloys.
Article
Nanoscience & Nanotechnology
Jin Tian, Yake Wu, Tinghui Cao, Jianbo Pang, Xu Zhang, Feng Jiang
Summary: This study investigates the phase evolution in VCoNi medium entropy alloy via tensile deformation at different temperatures and reveals its impact on mechanical behaviors. The results show that diverse phase transitions can be stimulated, and the influence of strain accumulation and Co segregation on phase transformation is discussed.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Chemistry, Physical
Unhae Lee, Jae Wung Bae
Summary: This study focused on the development of nanosized precipitates in Fe-71.25(CoCrMnNi)(23.75)Cu3Al2 maraging medium-entropy alloy (MEA). The nanosized precipitates enriched with Cu, with a diameter of approximately 5 nm, significantly increased the hardness of the alloy. The alloy with a BCC lath martensite structure with B2 intermetallics exhibited remarkable mechanical properties, achieving the highest Vickers microhardness of 597 HV, compressive yield strength of 2079 MPa, and ultimate compressive strength of 2843 MPa in the Aged_7h sample.
Article
Materials Science, Multidisciplinary
Jian Wu, Xiaoyan Liu, Heguo Zhu
Summary: The conflict between strength and ductility in structural materials has always been a challenge. It has been found that introducing nano-scaled precipitates through composition design can help achieve a balance between strength and ductility. In this study, FeCoNi-based medium-entropy alloys with Al and Ti combination addition were prepared and their phase constitution, microstructural changes, and mechanical properties were investigated. By adjusting the Al/Ti ratio, the as-cast Ni0.6CoFe1.6 MEA exhibited a good combination of strength and ductility, with the Al0.2Ti0.1 MEA showing the highest yield and ultimate tensile strength, as well as an acceptable failure strain.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Chemistry, Multidisciplinary
Thakur Prasad Yadav, Cristiano F. Woellner, Tiva Sharifi, Shyam Kanta Sinha, Lu-lu Qu, Amey Apte, N. K. Mukhopadhyay, O. N. Srivastava, Robert Vajtai, Douglas Soares Galvao, Chandra Sekhar Tiwary, Pulickel M. Ajayan
Article
Chemistry, Physical
S. S. Mishra, T. P. Yadav, N. K. Mukhopadhyay, O. N. Srivastava
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2020)
Article
Chemistry, Physical
S. S. Mishra, T. P. Yadav, Ram Manohar Yadav, Anand B. Puthirath, Liangzi Deng, Moein Adnani, Ching-Wu Chu, Robert Vajtai, P. M. Ajayan, Krishanu Biswas, N. K. Mukhopadhyay, O. N. Srivastava
Summary: Heusler alloys exhibit the structure of an ordered compound with most metallic properties, potentially driven by various magnetic exchange mechanisms. This study investigated the structural and magnetic properties of Fe50Mn25Al25-xGax alloys, showing that substitution of Al by Ga leads to lattice expansion in the L2(1) crystal structure and affects the magnetic moment, resulting in an increase in antiferromagnetic behavior with Ga content, as well as a decrease in Curie temperature. Additionally, a second-order magnetic phase transition was observed in these alloys above room temperature.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Anil Kumar, Santosh Kumar, Nilay Krishna Mukhopadhyay, Anshul Yadav, Virendra Kumar, Jerzy Winczek
Summary: The study investigated the extensive wear behavior of SiC reinforced magnesium alloy composites fabricated through the stir casting process. The findings revealed that the SiC reinforced composites exhibited higher microhardness, lower wear rate, and coefficient of friction compared to the unreinforced alloy. Different wear mechanisms were observed at various sliding velocities and loads, with adhesion and thermal softening/melting dominating at higher speeds and loads. Additionally, plastic deformation and smearing were found to occur at higher loads and sliding velocities.
Article
Chemistry, Physical
R. Rawat, A. Tiwari, N. Arun, S. V. S. Nageswara Rao, A. P. Pathak, Yagnesh Shadangi, N. K. Mukhopadhyay, S. Venugopal Rao, A. Tripathi
Summary: Nanosecond laser pulses were used to synthesize Cu/CuO/Fe3O4 and Al2O3 nanocomposites by ablating Al-Cu-Fe quasicrystal (QC) in two different solvents, which showed that the solvent choice can impact the structural and morphological transformations of the nanoparticles.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Nandini Singh, Yagnesh Shadangi, Vikas Shivam, Nilay Krishna Mukhopadhyay
Summary: The Equiatomic MgAlSiCrFeNi low-density high-entropy alloy was prepared through mechanical alloying and spark plasma sintering. Analysis using various techniques revealed the formation of a BCC phase and undissolved Si after milling. DSC experiments showed multiple exothermic heating events corresponding to phase transformations, in agreement with XRD results.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Metallurgy & Metallurgical Engineering
Trishita Roy, Vikas Shivam, Kausik Chattopadhyay, R. Manna, N. K. Mukhopadhyay
Summary: Pre-alloyed 316L austenitic stainless steel composite powders with yttria were synthesized using mechanical alloying. The milled powders contained nano-yttria dispersed in the austenitic stainless steel matrix, resulting in enhanced compressive strength and hardness. This enhancement was primarily attributed to dispersion strengthening/hardening mechanisms.
TRANSACTIONS OF THE INDIAN INSTITUTE OF METALS
(2021)
Article
Metallurgy & Metallurgical Engineering
T. P. Yadav, Harshit Agarwal, M. A. Shaz, N. K. Mukhopadhyay
Summary: This study investigates the synthesis and stability of a ternary complex metallic alloy in the Al-Cu-Ta system. The alloy exhibits a high hardness and high-temperature stability, making it a potential candidate for hard and tough coating materials.
TRANSACTIONS OF THE INDIAN INSTITUTE OF METALS
(2022)
Review
Multidisciplinary Sciences
N. K. Mukhopadhyay, Thakur Prasad Yadav
Summary: Quasicrystals are a new class of intermetallics with long-range quasiperiodic ordering, which have attracted research interest over the last 3 decades. The unique structural complexities and physical/mechanical properties of quasicrystals make them potential candidates for various applications.
JOURNAL OF THE INDIAN INSTITUTE OF SCIENCE
(2022)
Article
Chemistry, Physical
Abhishek Kumar, Thakur Prasad Yadav, Nilay Krishna Mukhopadhyay
Summary: In this study, the synthesis, structure, and hydrogen storage behavior of a high-entropy Ti-Zr-V-Cr-Ni equiatomic intermetallic alloy were investigated. The alloy exhibited reversible and stable hydrogen storage capacity, demonstrating the potential for developing high-entropy intermetallic materials for hydrogen storage.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Priyatosh Pradhan, Yagnesh Shadangi, Vikas Shivam, N. K. Mukhopadhyay
Summary: The present investigation focuses on the phase evolution, microstructure, thermal stability, and microhardness properties of an equiatomic quinary high entropy alloy Cr-Mn-Fe-Co-Mo. The alloy was synthesized via mechanical alloying and pressure-less sintering. The phase formation and composition were analyzed using X-ray diffraction, electron microscopy, and differential thermal analysis. The sintered sample exhibited the coexistence of four stable phases and high hardness and Young's modulus.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Metallurgy & Metallurgical Engineering
Vivek Kumar Pandey, Yagnesh Shadangi, Vikas Shivam, Joysurya Basu, Kausik Chattopadhyay, Bhaskar Majumdar, B. N. Sarma, Nilay Krishna Mukhopadhyay
Summary: An equiatomic quinary MgAlMnFeCu high-entropy alloy was successfully synthesized by mechanical alloying, and after spark plasma sintering it exhibited exceptional hardness and compressive strength while maintaining relatively low density. Various thermodynamic parameters were considered to understand the phase evolution and stability during the mechanical alloying process.
TRANSACTIONS OF THE INDIAN INSTITUTE OF METALS
(2021)
