Phase relationships in an Al3 (Ti,V) based in-situ composite |
| |
Authors: | Woong-Seong Chang BC Muddle |
| |
Institution: | Department of Materials Engineering, Monash University, Clayton, Victoria 3168, Australia |
| |
Abstract: | The phases and the crystallographic relationships between phases observed in an Al70Ti10V20 alloy following chill casting and post-solidification heat treatment have been characterized using analytical transmission electron microscopy and electron diffraction. The chill-cast microstructure comprised a mixture of primary dendrites of δ-Al3 (Ti,V) and interdendritic eutectic zones in which the continuous phase was δ-Al3 (Ti,V) and the rode-like discontinuous phase was ζ-Al8V5. Following isothermal heat treatments in the temperature range 1073–1273 K, a uniform distribution of rod-like particles was observed to develop throughout the δ matrix and a phase transformation was detected within the dispersed particles, as the intermetallic ζ phase was replaced by b.c.c.β-(Ti,V) metallic solid solution. This transformation was typically complete within 100 hr at 1073 K, leading to the formation of an in-situ composite consisting of a uniform dispersion of metallic β-phase in a brittle Al3(Ti,V) intermetallic matrix. The orientation relationship between the discontinuous β-(Ti,V) particles and the DO22δ-Al3(Ti,V) matrix involved parallelism of the closest-packed planes and close-packed directions in those planes, i.e. (110)β//(112)δ(DO22) and
11]β//
10]δ(DO22). |
| |
Keywords: | Intermetallic phase trialuminide in-situ composite orientation relationship transmission electron microscopy electron diffraction |
本文献已被 ScienceDirect 等数据库收录! |
|