TY - JOUR
T1 - In situ assessment of isochronal phase transformations in a lamellar Ti–5Al–5Mo-5V–3Cr–1Zr alloy using synchrotron X-ray diffraction
AU - Callegari, Bruna
AU - Campo, Lucia
AU - Aristizabal, Katherine
AU - Guitar, Maria Agustina
AU - Warchomicka, Fernando Gustavo
AU - Coelho, Rodrigo Santiago
AU - Brito, Pedro Paiva
AU - Soldera, Flavio
AU - Mücklich, Frank
AU - Cavalcanti Pinto, Haroldo
N1 - Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2021/2/5
Y1 - 2021/2/5
N2 - Phase transformations in a lamellar Ti–5Al–5Mo–5V–3Cr–1Zr (Ti-55531) alloy upon heating at continuous rates of 5, 20 and 100 °C/min has been studied by in situ high energy X-ray diffraction (HEXRD), aided by scanning and transmission electron microscopy, atom probe tomography and hardness measurements. During slow heating, the β phase has shown a behavior suggestive of additional transformations other than the continuous α → β decomposition observed at higher heating rates. Such behavior has been attributed to the precipitation of an embryonic isothermal ω phase. APT analyses have shown that no elemental partitioning occurs between the β matrix and the lamellar α phase, but it does between β and grain boundary α, suggesting that ω phase precipitates with solute rejection in regions outside lamellar colonies embedded in an enriched matrix. Above 500 °C, diffusion becomes significantly enhanced and α decomposition takes place.
AB - Phase transformations in a lamellar Ti–5Al–5Mo–5V–3Cr–1Zr (Ti-55531) alloy upon heating at continuous rates of 5, 20 and 100 °C/min has been studied by in situ high energy X-ray diffraction (HEXRD), aided by scanning and transmission electron microscopy, atom probe tomography and hardness measurements. During slow heating, the β phase has shown a behavior suggestive of additional transformations other than the continuous α → β decomposition observed at higher heating rates. Such behavior has been attributed to the precipitation of an embryonic isothermal ω phase. APT analyses have shown that no elemental partitioning occurs between the β matrix and the lamellar α phase, but it does between β and grain boundary α, suggesting that ω phase precipitates with solute rejection in regions outside lamellar colonies embedded in an enriched matrix. Above 500 °C, diffusion becomes significantly enhanced and α decomposition takes place.
KW - Titanium alloys
KW - High energy X-ray diffraction
KW - Atom probe tomography
KW - Phase transformations
KW - Element partitioning
UR - http://www.sciencedirect.com/science/article/pii/S0925838820334691
UR - http://www.scopus.com/inward/record.url?scp=85091218959&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.jallcom.2020.157105
DO - https://doi.org/10.1016/j.jallcom.2020.157105
M3 - Article
VL - 853
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
SN - 0925-8388
M1 - 157105
ER -