Asymmetric accumulative roll bonding of aluminium-titanium composite sheets
(2013) In Materials Science & Engineering: A 576. p.306-315- Abstract
Aluminium-titanium (Al/Ti) composite sheets were fabricated via asymmetric accumulative roll bonding (AARB), which capitalises on additional shear to enhance plastic deformation. Multi-layers of Al alloy (AA1050) and commercially-pure Ti sheets were alternatively stacked and rolled-bonded with varied roll diameter ratios (dr) ranging from 1 to 2, for up to four passes. Annealing of selected composite sheets was subsequently carried out at 600°C for 24h to compare the rates of solid-state diffusion reactions between Al and Ti components. Mechanical tests revealed that both tensile strength and ductility of the sheets increase systematically with dr. The microstructures and the Al/Ti interfaces of the sheets were... (More)
Aluminium-titanium (Al/Ti) composite sheets were fabricated via asymmetric accumulative roll bonding (AARB), which capitalises on additional shear to enhance plastic deformation. Multi-layers of Al alloy (AA1050) and commercially-pure Ti sheets were alternatively stacked and rolled-bonded with varied roll diameter ratios (dr) ranging from 1 to 2, for up to four passes. Annealing of selected composite sheets was subsequently carried out at 600°C for 24h to compare the rates of solid-state diffusion reactions between Al and Ti components. Mechanical tests revealed that both tensile strength and ductility of the sheets increase systematically with dr. The microstructures and the Al/Ti interfaces of the sheets were analysed in detail using TEM, SEM and FIB techniques. It is shown that not only does AARB lead to a more refined grain size of the Al matrix but also it promotes the development of a nanostructured surface layer on Ti that comprises crystallites of 50-100nm in size, which is otherwise absent in the case of symmetric ARB (i.e. dr=1). The AARB-processed sheets exhibit a larger thickness of the interdiffusion layer at the Al/Ti interfaces than the counterparts processed via the symmetric ARB route, the difference being in excess of 15%. The effects and the implications of AARB processing on mechanical behaviour and diffusion kinetics are discussed with respect to the microstructural evolutions.
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- author
- Ng, Hoi Pang; Przybilla, Thomas; Schmidt, Christian; Lapovok, Rimma; Orlov, Dmitry; Höppel, Heinz Werner and Göken, Mathias
- publishing date
- 2013-08-01
- type
- Contribution to journal
- publication status
- in press
- subject
- keywords
- Al-Ti, Asymmetric accumulative roll bonding, Diffusion, Mechanical properties, Transmission electron microscopy
- in
- Materials Science & Engineering: A
- volume
- 576
- pages
- 10 pages
- publisher
- Elsevier
- external identifiers
-
- scopus:84877075055
- ISSN
- 0921-5093
- DOI
- 10.1016/j.msea.2013.04.027
- language
- English
- LU publication?
- no
- id
- 4396f534-351c-4222-9a5b-52b41bff89fd
- date added to LUP
- 2016-06-20 15:58:12
- date last changed
- 2018-01-07 11:18:23
@article{4396f534-351c-4222-9a5b-52b41bff89fd, abstract = {<p>Aluminium-titanium (Al/Ti) composite sheets were fabricated via asymmetric accumulative roll bonding (AARB), which capitalises on additional shear to enhance plastic deformation. Multi-layers of Al alloy (AA1050) and commercially-pure Ti sheets were alternatively stacked and rolled-bonded with varied roll diameter ratios (d<sub>r</sub>) ranging from 1 to 2, for up to four passes. Annealing of selected composite sheets was subsequently carried out at 600°C for 24h to compare the rates of solid-state diffusion reactions between Al and Ti components. Mechanical tests revealed that both tensile strength and ductility of the sheets increase systematically with d<sub>r</sub>. The microstructures and the Al/Ti interfaces of the sheets were analysed in detail using TEM, SEM and FIB techniques. It is shown that not only does AARB lead to a more refined grain size of the Al matrix but also it promotes the development of a nanostructured surface layer on Ti that comprises crystallites of 50-100nm in size, which is otherwise absent in the case of symmetric ARB (i.e. d<sub>r</sub>=1). The AARB-processed sheets exhibit a larger thickness of the interdiffusion layer at the Al/Ti interfaces than the counterparts processed via the symmetric ARB route, the difference being in excess of 15%. The effects and the implications of AARB processing on mechanical behaviour and diffusion kinetics are discussed with respect to the microstructural evolutions.</p>}, author = {Ng, Hoi Pang and Przybilla, Thomas and Schmidt, Christian and Lapovok, Rimma and Orlov, Dmitry and Höppel, Heinz Werner and Göken, Mathias}, issn = {0921-5093}, keyword = {Al-Ti,Asymmetric accumulative roll bonding,Diffusion,Mechanical properties,Transmission electron microscopy}, language = {eng}, month = {08}, pages = {306--315}, publisher = {Elsevier}, series = {Materials Science & Engineering: A}, title = {Asymmetric accumulative roll bonding of aluminium-titanium composite sheets}, url = {http://dx.doi.org/10.1016/j.msea.2013.04.027}, volume = {576}, year = {2013}, }