Microstructural Characterization of Melt Extracted High-Nb-Containing TiAl-Based Fiber
نویسندگان
چکیده
The microstructure of melt extracted Ti-44Al-8Nb-0.2W-0.2B-1.5Si fiber were investigated. When the rotation speed increased from 2000 to 2600 r/min, the appearance of the wire was uniform with no Rayleigh-wave default. The structure was mainly composed of fine α₂ (α) phase dendritic crystal and a second phase between dendrite arms and grain boundaries. The precipitated second phases were confirmed to be Ti₅Si₃ from the eutectic reaction L→Ti₅Si₃ + α and TiB. As the lower content of Si and higher cooling rate, a divorced eutectic microstructure was obtained. Segregation of Ti, Nb, B, Si, and Al occurred during rapid solidification.
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عنوان ژورنال:
دوره 10 شماره
صفحات -
تاریخ انتشار 2017