Room temperature and high-temperature properties of extruded Ti-4Fe-3W/2TiC composites in α+β and β phases

• Main Authors: Bahador, Abdollah, Yurtsever, Ayhan, Amrin, Astuty, Kariya, Shota, Umeda, Junko, Shen, Jianghua, Chen, Biao, Fukuma, Takeshi, Kondoh, Katsuyoshi
• Format: Article
• Language: English
• Published: Elsevier Ltd 2022
• Subjects: Q Science (General)
• Online Access: http://eprints.utm.my/103000/1/AstutyAmrin2022_RoomTemperatureandHighTemperatureProperties.pdf; http://eprints.utm.my/103000/; http://dx.doi.org/10.1016/j.matdes.2022.110901

Considering the high strength of titanium matrix composites (TMCs) at room and elevated temperatures, the aim of this study was to develop novel TMC Ti-4Fe-3W/2TiC (wt%) utilizing powder metallurgy and subsequent extrusion at different temperatures: the two-phase (α+β) and pure β phase regions. The TiC particle dispersion was almost identical in both composites with variation in the size distribution. However, there was a significant difference in the morphology of the α phase in the matrix. The α+β-extruded composite exhibited globular αp (grain size: 0.7 μm); in contrast, the β-extruded phase showed acicular αs (grain size: 1.5 μm). Additionally, α-Ti was the predominant phase in contact with TiC particles due to the semi-coherent relationship between these two phases. A remarkably high yield strength (1215 MPa) was achieved at room temperature in the α+β -extruded composite, while the β-extruded composite exhibited consistently improved strength at high temperatures. Morphological characterization using atomic force microscopy (AFM) revealed the β phase was slightly harder than the α phase, probably due to the solid solution of Fe and W that predominant in the β phase.