Criteria for fast and selective α precipitation at β grain boundaries in Ti-alloys Consequence for in-service microstructures
The potential for β grain boundaries (GBs) to give rise to large Widmanstätten colonies was determined through the observation of a large amount of precipitates at β GBs in a β-metastable titanium alloy using electron backscatter imaging and diffraction. The most critical boundaries are those which...
Main Authors: | , , , , |
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Format: | Article |
Language: | English |
Published: |
EDP Sciences
2020-01-01
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Series: | MATEC Web of Conferences |
Online Access: | https://www.matec-conferences.org/articles/matecconf/pdf/2020/17/matecconf_ti2019_12040.pdf |
Summary: | The potential for β grain boundaries (GBs) to give rise to large Widmanstätten colonies was determined through the observation of a large amount of precipitates at β GBs in a β-metastable titanium alloy using electron backscatter imaging and diffraction. The most critical boundaries are those which transform early and where a type of Variant Selection (VS) called double Burgers VS occurs. This mechanisms take place at ‘special’ β boundaries misoriented so that an α precipitate can be related to both grains through the Burgers relation. It was shown that the most critical GBs have a disorientation at an angle of less than 10° from 49.5°/<110> or 60°/<110>. A simulation study allowed those boundaries to be quantifed in crystallographic textures typical of industrial products. Those texture have then been discussed as a function of their potential to form large Widmanstätten colonies. |
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ISSN: | 2261-236X |