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Singh AK, Wang W, Panda DP, Bagchi D, Goud D, Ray B, He J, Peter SC. Cobalt-Induced Phase Transformation of Ni 3Ga 4 Generates Chiral Intermetallic Co 3Ni 3Ga 8. J Am Chem Soc 2023; 145:1433-1440. [PMID: 36580662 DOI: 10.1021/jacs.2c12366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The scientific community has found immense difficulty to focus on the generation of chiral intermetallics compared to the chiral molecular structure, probably due to the technical difficulty in producing them as no general controlled protocol is available. Herein, using a conventional metal flux technique, we have discovered a new ternary intermetallic Co3Ni3Ga8, substituting Co at the Ni sublattice in a highly symmetric Ni3Ga4 (Ia3̅d). Co3Ni3Ga8 crystallizes in the I4132 space group, a Sohncke type, and can host the chiral structure. To the best of our knowledge, this is the first report of a ternary intermetallic crystallizing in this space group. The chiral structure of Co3Ni3Ga8 is comprehensively mapped by various techniques such as single-crystal X-ray diffraction (XRD), synchrotron powder XRD, X-ray absorption spectroscopy (XAS), scanning transmission electron microscopy (STEM) and theoretically studied using density functional theory. The discovery of this chiral compound can inspire the researchers to design hidden ternary chiral intermetallics to study the exotic electrical and magnetic properties.
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Affiliation(s)
- Ashutosh Kumar Singh
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
| | - Wu Wang
- Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong 518055, PR China
| | - Debendra Prasad Panda
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
| | - Debabrata Bagchi
- School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
| | - Devender Goud
- School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
| | - Bitan Ray
- School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
| | - Jiaqing He
- Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong 518055, PR China
| | - Sebastian C Peter
- School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
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Effects of Annealing on the Microstructure and Wear Resistance of Laser Cladding CrFeMoNbTiW High-Entropy Alloy Coating. CRYSTALS 2021. [DOI: 10.3390/cryst11091096] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In this study, a CrFeMoNbTiW high-entropy alloy (HEA) coating was prepared on a Q245R steel (American grade: SA515 Gr60) substrate by means of laser cladding. The effects of annealing temperature on the microstructure and wear resistance of the CrFeMoNbTiW coating were investigated using X-ray diffraction (XRD), a scanning electron microscope (SEM), a Vickers hardness tester and a roller friction wear tester. The results showed that the coating was mainly composed of body-centered cubic (BCC) solid solution and face-centered cubic (FCC) structural (Nb,Ti)C carbides prior to annealing, exhibiting an interdendritic structure and needlelike dendritic crystal structure with average microhardness of 682 HV0.2. The coarsening of the dendrite arms increased gradually after a 10-h long annealing treatment at 800 °C, 900 °C and 1000 °C, and a small amount of Laves phase was produced. After annealing, the highest microhardness value of the as-annealed coating reached 1176 HV0.2, which represents an increase of approximately 72.5% compared to that of the as-deposit coating. The wear resistance testing results imply that this type of coating retains good wear resistance following the annealing treatment and that its wear resistance increases in proportion to the annealing temperature in a range from 800 °C to 1000 °C.
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