Deakin University
Browse

File(s) under permanent embargo

Microstructure and Texture Evolution During Symmetric and Asymmetric Rolling of a Martensitic Ti-6Al-4V Alloy

Version 2 2024-06-04, 02:07
Version 1 2015-11-27, 11:08
journal contribution
posted on 2024-06-04, 02:07 authored by Q Chao, Peter HodgsonPeter Hodgson, Hossein BeladiHossein Beladi
In the current study, the effect of deformation mode (i.e., symmetric vs asymmetric rolling) on the extent of grain refinement and texture development in Ti-6Al-4V was examined through warm rolling of a martensitic starting microstructure. During rolling, the initial martensitic lath structure was progressively fragmented, primarily through continuous dynamic recrystallization. This eventually led to an ultrafine-grained (UFG) microstructure composed of equiaxed grains with a mean size of 180 to 230 nm, mostly surrounded by high-angle grain boundaries. Depending on the rolling reduction and deformation mode (symmetric and asymmetric), the rolled specimens displayed different layer morphologies throughout the specimen thickness: a fully UFG surface layer, a partial UFG transition layer, and a partially fragmented lath interior layer. Due to a higher level of effective strain and continuous rotation of the principle axis, asymmetric rolling resulted in a greater extent of grain refinement compared with symmetric rolling at a given thermomechanical condition. A bulk UFG structure was successfully obtained using 70 pct asymmetric rolling. In addition, the rolling texture exhibited various characteristics throughout the thickness due to a different combination of shear and compressive strains. Principally, the basal texture component was displaced from the normal toward rolling direction during asymmetric rolling, differing from the symmetric rolling textures.

History

Journal

Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science

Volume

47

Pagination

531-545

Location

New York, N.Y.

ISSN

1073-5623

eISSN

1543-1940

Language

English

Publication classification

C Journal article, C1 Refereed article in a scholarly journal

Copyright notice

2015, Minerals, Metals & Materials Society and ASM International

Issue

1

Publisher

SPRINGER