Grain refinement in beta-solidifying Ti44Al8Nb1B

被引：62
作者：
Hu, D. [1 ]
Yang, C. [1 ]
Huang, A. [2 ]
Dixon, M. [2 ]
Hecht, U. [3 ]
机构：
[1] Univ Birmingham, Interdisciplinary Res Ctr Mat, Birmingham B15 2TT, W Midlands, England
[2] Rolls Royce PLC, Derby DE24 8BJ, England
[3] ACCESS Mat & Proc, D-52072 Aachen, Germany
来源：
INTERMETALLICS | 2012年 / 23卷
基金：
英国工程与自然科学研究理事会;
关键词：
Titanium aluminides; based on TiAl; Phase identification; Phase transformation; Crystal growth; Microstructure; TIAL-BASED ALLOYS; TITANIUM ALUMINIDES; TENSILE DUCTILITY; BORON ADDITION; FE;
D O I：
10.1016/j.intermet.2011.12.022
中图分类号：
O64 [物理化学（理论化学）、化学物理学];
学科分类号：
070304 ; 081704 ;
摘要：
Grain refinement in Ti44Al8Nb1B was studied using directional solidification technique and SEM EBSD analysis. Grain refinement occurred during beta-to-alpha transformation through boride assisted alpha nucleation mechanism rather than during solidification. Burgers and non-Burgers alpha2 grain coexisted and they were inoculated by boride precipitates. The orientation relationship between alpha and the B27 TiB precipitates is <11<(2)over bar>0>(alpha 2)//[010](B27) and (0001)(alpha 2)//(001)(B27). The Burgers alpha variants were inoculated by the boride precipitates having an OR with beta phase and the OR was deduced as (001)(TiB)//{110)(beta), (010)(TiB)//{111)(beta) and (100)(TiB)//{211}(beta). (C) 2012 Elsevier Ltd. All rights reserved.
引用
收藏
页码：49 / 56
页数：8
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