Inhomogeneous Precipitation of the α-Phase in Ti15Mo Alloy Deformed by ECAP

Abstract:

A metastable β-titanium alloy, Ti15Mo was subjected to equal channel angular pressing (ECAP). The resulting microstructure of the material is inhomogeneous consisting of micrometer size β-grains with deformed bands containing ultra-fine β-grains. The ECAP-deformed sample was subjected to thermal treatment in order to elucidate the difference in morphology of the α-phase precipitation in deformed and non-deformed materials. The α-phase formation is accelerated in areas with higher concentration of lattice defects. The detail investigation by transmission electron microscopy revealed equixed α-phase formation in deformed bands. In the transition area between deformed band and β-matrix grain boundary α-phase forms while in the interior of the β-grains the α-phase precipitation is suppressed.

• Periodical: Materials Science Forum (Volume 941)
• Pages: 1183-1188
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.941.1183
• Online since: December 2018
• Authors: Kristína Bartha*, Anna Veverková, Josef Stráský, Peter Minárik, Jozef Veselý, Veronika Polyakova, Irina Semenova, Miloš Janeček
• Keywords: Metastable Beta Titanium Alloys, Phase Transformation, Severe Plastic Deformation, α-Phase Precipitation

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