Synchrotron diffraction analysis of retained austenite in welded transformation induced plasticity (TRIP) steels
Author
Summary, in English
A quantitative analysis of the retained austenite (RA) fractions in gas tungsten arc welded silicon and aluminium containing transformation induced plasticity steels was carried out by synchrotron X-ray diffraction measurements. The variation in RA transverse to the weld line was measured to study the effect of weld thermal cycles on the stabilisation of austenite in the heat affected zone (HAZ) and the fusion zone (FZ). The results showed that the FZ of silicon based steels contained a higher amount of RA (similar to 7%) than aluminium based steels, which contained only similar to 4%. During the solidification of the weld pool, aluminium was found to partition to solidifying delta-ferrite and to stabilise the soft delta-ferrite grains at the fusion boundaries. Owing to this partitioning, the HAZ was enriched in carbon and the RA content was found to increase with distance from the fusion boundaries. In contrast, this partitioning behaviour was not present in silicon based transformation induced plasticity steels and a lesser amount of RA was found in the coarse grained HAZ than in the FZ.
Department/s
Publishing year
2012
Language
English
Pages
146-154
Publication/Series
Science and Technology of Welding and Joining
Volume
17
Issue
2
Document type
Journal article
Publisher
Maney Publishing
Topic
- Natural Sciences
- Physical Sciences
Keywords
- TRIP steels
- Retained austenite
- Synchrotron diffraction
- GTA welding
Status
Published
ISBN/ISSN/Other
- ISSN: 1362-1718