In-situ investigation of phase transformations in ultra-fine grained Ti15Mo alloy

A metastable ß solution treated Ti15Mo alloy was deformed by high pressure torsion (HPT) resulting in a severely deformed microstructure with high density of lattice defects. In order to gain insight into the kinetics of phase transformations, both non-deformed and HPT-deformed materials were studie...

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Detalles Bibliográficos
Autores: Bartha, Kristína, Stráský, Josef, Barriobero Vila, Pere|||0000-0002-4412-3729, Šmilauerová, Jana, Vesely, Jozef, Semenova, Irina, Polyakova, Veronika, Janecek, Miloš
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/387353
Acceso en línea:https://hdl.handle.net/2117/387353
https://dx.doi.org/10.1016/j.jallcom.2021.159027
Access Level:acceso abierto
Palabra clave:Titanium alloys
Titani -- Aliatges
Àrees temàtiques de la UPC::Enginyeria dels materials
Descripción
Sumario:A metastable ß solution treated Ti15Mo alloy was deformed by high pressure torsion (HPT) resulting in a severely deformed microstructure with high density of lattice defects. In order to gain insight into the kinetics of phase transformations, both non-deformed and HPT-deformed materials were studied in-situ during linear heating; phase evolution was investigated using high energy synchrotron X-ray diffraction (HEXRD) complemented by the measurement of electrical resistance. It was shown that in the non-deformed material the dissolution of the ¿ phase is followed by precipitation of the a phase during linear heating. In contrast, in the HPT-deformed material the nucleation of the a phase is shifted to lower temperatures, resulting in the coexistence of all three ß, ¿, and a phases at ~550 °C. Moreover, in HPT-deformed samples, the growth of a particles is accelerated due to high density of dislocations and grain boundaries. Post-mortem observations of selected samples revealed that the microstructure of the HPT-deformed material after heating up to 650 °C remains ultra-fine grained with equiaxed grains of a phase.