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Erschienen in: Journal of Materials Engineering and Performance 7/2018

20.06.2018

Microstructures and Mechanical Behavior of Ti3SiC2/Al2O3-Ni Composites Synthesized by Pulse Discharge Sintering

verfasst von: Zeinab Pourali, Mohammad Reza Sovizi, Mohammad Reza Yaftian, Zeinab Amiri, Seyyed Mohsen Emami, Hosein Eslami Shahed

Erschienen in: Journal of Materials Engineering and Performance | Ausgabe 7/2018

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Abstract

High-purity Ti3SiC2 and Ti3SiC2/Al2O3-Ni composites with different Al2O3-Ni contents were fabricated using pulse discharge sintering (PDS) of a mechanical alloyed powder mixture. The synthesis process of monolithic Ti3SiC2 was studied through displacement temperature–time (DTT) curve, displacement rate–time and displacement rate–temperature diagrams obtained during the PDS process. It was found that TiCx and Ti5Si3Cy are the intermediate phases and the PDS process completed after 20 min at 1350 °C. The results showed that in Ti3SiC2/Al2O3-Ni composite, the Ni part of Al2O3-Ni leads to decomposition of Ti3SiC2 to TiCx, Ti5Si3Cy and Ni(Si)x. No evidence was detected in the reaction between Al2O3 and Ti3SiC2. The density and hardness of the composites are higher than monolithic Ti3SiC2 due to the production of reinforcing phases. The composite showed lower flexural strength and higher compressive strength than monolithic Ti3SiC2.

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Metadaten
Titel
Microstructures and Mechanical Behavior of Ti3SiC2/Al2O3-Ni Composites Synthesized by Pulse Discharge Sintering
verfasst von
Zeinab Pourali
Mohammad Reza Sovizi
Mohammad Reza Yaftian
Zeinab Amiri
Seyyed Mohsen Emami
Hosein Eslami Shahed
Publikationsdatum
20.06.2018
Verlag
Springer US
Erschienen in
Journal of Materials Engineering and Performance / Ausgabe 7/2018
Print ISSN: 1059-9495
Elektronische ISSN: 1544-1024
DOI
https://doi.org/10.1007/s11665-018-3452-1

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