Kinetics of grain growth in Ti-2.7Al-5.7Fe-6Mo-6V alloy
The metastable (βTi) alloy Ti-2.7Al-5.7Fe-6Mo-6V (wt%) was produced by semi-centrifugal casting of blended elemental powders. The phases were identified by X-ray diffraction (XRD), and overall composition was measured by X-ray fluorescence (XRF). The beta transus was determined by different...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
University of Belgrade, Technical Faculty, Bor
2017-01-01
|
| Series: | Journal of Mining and Metallurgy. Section B: Metallurgy |
| Subjects: | |
| Online Access: | http://www.doiserbia.nb.rs/img/doi/1450-5339/2017/1450-53391700041M.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832573692382543872 |
|---|---|
| author | Mutava T.D. Cornish L.A. Sigalas I. |
| author_facet | Mutava T.D. Cornish L.A. Sigalas I. |
| author_sort | Mutava T.D. |
| collection | DOAJ |
| description | The metastable (βTi) alloy Ti-2.7Al-5.7Fe-6Mo-6V (wt%) was produced by
semi-centrifugal casting of blended elemental powders. The phases were
identified by X-ray diffraction (XRD), and overall composition was measured
by X-ray fluorescence (XRF). The beta transus was determined by differential
thermal analysis (DTA) and optical microscopy. The cast alloys were annealed
at different temperatures under argon, up to 900oC, where they were in the
solution-treated state, and the solution-treated alloys were aged between
400oC and 600oC. The kinetics of grain growth during heat treatment of the
as-cast and solution-treated alloys was investigated by metallography, using
the grain intercept method. Grain growth depended on whether the matrix was
(αTi) or (βTi), and on the competing precipitate dissolution, or nucleation
and growth processes. The as-cast alloy had a mean grain size of 19 ± 7μm,
which increased to 63 ± 21μm after heat treating at 500°C for 2h. The alloy
was duplex between 590°C and 800°C, and completely (βTi) above 800°C. After
solution treatment, the mean grain size was 40 ± 16 μm, which was smaller
than at the lower heat treatment temperatures. Following solution treatment,
the mean grain size increased with increasing ageing temperature, up to 66 ±
22μm after 2h at 600°C. The growth exponents were lower than the 0.5 for
normal grain growth in both cases, and there was an incubation period at
300°C and 400°C when the alloy was not solution-treated. Minimal grain growth
was observed close to the beta transus. |
| format | Article |
| id | doaj-art-56c44584ffbd498599faabd07e800372 |
| institution | Kabale University |
| issn | 1450-5339 2217-7175 |
| language | English |
| publishDate | 2017-01-01 |
| publisher | University of Belgrade, Technical Faculty, Bor |
| record_format | Article |
| series | Journal of Mining and Metallurgy. Section B: Metallurgy |
| spelling | doaj-art-56c44584ffbd498599faabd07e8003722025-02-02T03:17:20ZengUniversity of Belgrade, Technical Faculty, BorJournal of Mining and Metallurgy. Section B: Metallurgy1450-53392217-71752017-01-0153326327010.2298/JMMB170421041M1450-53391700041MKinetics of grain growth in Ti-2.7Al-5.7Fe-6Mo-6V alloyMutava T.D.0Cornish L.A.1Sigalas I.2University of the Witwatersrand, School of Chemical and Metallurgical Engineering, South Africa + DST-NRF Centre of Excellence in Strong Materials, hosted by the University of the Witwatersrand, South AfricaUniversity of the Witwatersrand, School of Chemical and Metallurgical Engineering, South Africa + DST-NRF Centre of Excellence in Strong Materials, hosted by the University of the Witwatersrand, South AfricaUniversity of the Witwatersrand, School of Chemical and Metallurgical Engineering, South Africa + DST-NRF Centre of Excellence in Strong Materials, hosted by the University of the Witwatersrand, South AfricaThe metastable (βTi) alloy Ti-2.7Al-5.7Fe-6Mo-6V (wt%) was produced by semi-centrifugal casting of blended elemental powders. The phases were identified by X-ray diffraction (XRD), and overall composition was measured by X-ray fluorescence (XRF). The beta transus was determined by differential thermal analysis (DTA) and optical microscopy. The cast alloys were annealed at different temperatures under argon, up to 900oC, where they were in the solution-treated state, and the solution-treated alloys were aged between 400oC and 600oC. The kinetics of grain growth during heat treatment of the as-cast and solution-treated alloys was investigated by metallography, using the grain intercept method. Grain growth depended on whether the matrix was (αTi) or (βTi), and on the competing precipitate dissolution, or nucleation and growth processes. The as-cast alloy had a mean grain size of 19 ± 7μm, which increased to 63 ± 21μm after heat treating at 500°C for 2h. The alloy was duplex between 590°C and 800°C, and completely (βTi) above 800°C. After solution treatment, the mean grain size was 40 ± 16 μm, which was smaller than at the lower heat treatment temperatures. Following solution treatment, the mean grain size increased with increasing ageing temperature, up to 66 ± 22μm after 2h at 600°C. The growth exponents were lower than the 0.5 for normal grain growth in both cases, and there was an incubation period at 300°C and 400°C when the alloy was not solution-treated. Minimal grain growth was observed close to the beta transus.http://www.doiserbia.nb.rs/img/doi/1450-5339/2017/1450-53391700041M.pdfGrain growthKineticsSolution-treatmentTimetal 125. |
| spellingShingle | Mutava T.D. Cornish L.A. Sigalas I. Kinetics of grain growth in Ti-2.7Al-5.7Fe-6Mo-6V alloy Journal of Mining and Metallurgy. Section B: Metallurgy Grain growth Kinetics Solution-treatment Timetal 125. |
| title | Kinetics of grain growth in Ti-2.7Al-5.7Fe-6Mo-6V alloy |
| title_full | Kinetics of grain growth in Ti-2.7Al-5.7Fe-6Mo-6V alloy |
| title_fullStr | Kinetics of grain growth in Ti-2.7Al-5.7Fe-6Mo-6V alloy |
| title_full_unstemmed | Kinetics of grain growth in Ti-2.7Al-5.7Fe-6Mo-6V alloy |
| title_short | Kinetics of grain growth in Ti-2.7Al-5.7Fe-6Mo-6V alloy |
| title_sort | kinetics of grain growth in ti 2 7al 5 7fe 6mo 6v alloy |
| topic | Grain growth Kinetics Solution-treatment Timetal 125. |
| url | http://www.doiserbia.nb.rs/img/doi/1450-5339/2017/1450-53391700041M.pdf |
| work_keys_str_mv | AT mutavatd kineticsofgraingrowthinti27al57fe6mo6valloy AT cornishla kineticsofgraingrowthinti27al57fe6mo6valloy AT sigalasi kineticsofgraingrowthinti27al57fe6mo6valloy |