Microstructural Characterization of Melt Extracted High-Nb-Containing TiAl-Based Fiber

Shuzhi Zhang; Shuling Zhang; Yanfei Chen; Jianchao Han; Changjiang Zhang; Xiaopeng Wang; Yuyong Chen

doi:10.3390/ma10020195

Microstructural Characterization of Melt Extracted High-Nb-Containing TiAl-Based Fiber

Materials (Basel). 2017 Feb 17;10(2):195. doi: 10.3390/ma10020195.

Authors

Shuzhi Zhang^{1

2}, Shuling Zhang³, Yanfei Chen⁴, Jianchao Han⁵, Changjiang Zhang^{6

7}, Xiaopeng Wang⁸, Yuyong Chen⁹

Affiliations

¹ School of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China. zhshzh1984@163.com.
² Shanxi Key Laboratory of Advanced Magnesium-based Materials, Taiyuan University of Technology, Taiyuan 030024, China. zhshzh1984@163.com.
³ School of Mechanical Engineering, Ningxia University, Ningxia 750021, China. slzhang1229@163.com.
⁴ Ningbo Branch of China Ordnance Academy, Ningbo 315000, China. yanfeichen@hotmail.com.
⁵ School of Mechanical Engineering, Taiyuan University of Technology, Taiyuan 030024, China. hanjianchao@tyut.edu.cn.
⁶ School of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China. zcj0408@163.com.
⁷ Shanxi Key Laboratory of Advanced Magnesium-based Materials, Taiyuan University of Technology, Taiyuan 030024, China. zcj0408@163.com.
⁸ National Key Laboratory for Precision Hot Processing of Metals, Harbin Institute of Technology, Harbin 150001, China. wangxiaopeng@hit.edu.cn.
⁹ National Key Laboratory for Precision Hot Processing of Metals, Harbin Institute of Technology, Harbin 150001, China. yychen@hit.edu.cn.

Abstract

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.

Keywords: TEM; Ti5Si3; divorced eutectic; intermetallics; melt extracted; rapid-solidification.