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Munawar A.♦, Sadeeda .♦, Asif V.♦, Jafri A.♦, Nisar F.♦, Wegener M.♦, Su J.♦, Kargl F.♦, Effect of Undercooling on the Microstructure and Mechanical Properties of Hyper-eutectic Ni–Sn Alloy,
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, ISSN: 1073-5623, DOI: 10.1007/s11661-023-07172-z, pp.1-9, 2023 Abstract:
In this study, container-less solidification of hyper-eutectic Ni–Sn alloy has been performed by using the electromagnetic levitation technique. The effect of undercooling on the formed microstructure and on the mechanical properties have been investigated. Growth velocities were determined by high-speed video-imaging of the solidification process. A step change in the growth velocities that are increasing with increasing undercooling is observed. This aligns with an observed first change in the microstructure between low and intermediate undercoolings. At the lower undercoolings, a pro-eutectic Ni3Sn phase along with lamellar eutectic structure in the inter-dendritic region is found. At intermediate undercooling of 100–150 K, a divorced eutectic microstructure is observed whereas at undercoolings above 165 K α-Ni precipitates are observed within β-Ni3Sn dendrites. Microhardness testing revealed higher strength for the lamellar phase as compared to the non-lamellar phase. Nano-indentation has been performed to determine the hardness and strength of individual phases in the microstructure. Affiliations:
| Munawar A. | - | other affiliation | | Sadeeda . | - | other affiliation | | Asif V. | - | other affiliation | | Jafri A. | - | other affiliation | | Nisar F. | - | other affiliation | | Wegener M. | - | other affiliation | | Su J. | - | other affiliation | | Kargl F. | - | other affiliation |
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| 2. |
Anwer Z.♦, Umer Malik A.♦, Nisar F.♦, Hafeez Muhammad A.♦, Yaqoob K.♦, Luo X.♦, Ahmad I.♦, Microstructure and mechanical properties of hot isostatic pressed tungsten heavy alloy with FeNiCoCrMn high entropy alloy binder,
Journal of Materials Research and Technology, ISSN: 2238-7854, DOI: 10.1016/j.jmrt.2022.12.078, Vol.22, pp.2897-2909, 2023Abstract:
Microstructural development and mechanical properties of tungsten heavy alloy, WHA, with FeNiCoCrMn high entropy alloy, HEA, binder were investigated and compared to conventional WHA using Fe–Ni binder. Both WHAs, with HEA and conventional Fe–Ni binders, were fabricated by hot isostatic pressing at a temperature of 1450 °C in an argon environment. Scanning electron microscopy revealed that WHA with HEA and conventional binders possessed uniform and well-refined microstructures. Energy dispersive spectroscopy and X-ray diffraction, XRD, spectroscopy validated the formation and composition of HEA, existing as a skeletal network surrounding tungsten grains. HEA binder exhibited an overall increase of 42% in micro Vickers hardness values. Furthermore, hardness values of the tungsten heavy alloy were also seen to rise when fabricated with HEA binder. However, WHA sample with HEA binder was seen to undergo faster strain hardening and a premature failure, leading to lower values of ultimate strength and reduced ductility. Keywords:
Tungsten heavy alloys, High entropy alloys, Hot isostatic pressing, Liquid phase sintering Affiliations:
| Anwer Z. | - | other affiliation | | Umer Malik A. | - | other affiliation | | Nisar F. | - | other affiliation | | Hafeez Muhammad A. | - | other affiliation | | Yaqoob K. | - | other affiliation | | Luo X. | - | other affiliation | | Ahmad I. | - | other affiliation |
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