Influence of High-Pressure Torsion on the Microstructure and the Hardness of a Ti-Rich High-Entropy Alloy

Abstract:

High-Pressure Torsion (HPT) is one of the most effective severe plastic deformation techniques in grain refinement. The goal of this study was to investigate the influence of HPT on the microstructure and hardness of a Ti-rich High-Entropy Alloy (HEA). The evolution of the grain size due to 1 turn of HPT was studied by transmission electron microscopy. Besides the refinement of the microstructure, a phase transition also occurred during HPT, as revealed by X-ray diffraction. The initial bcc structure transformed into a martensitic phase throughout the material. The features of this phase transformation were studied on a sample compressed to low strain values. The hardness as a function of the distance from the center in the HPT-processed disk was measured and correlated to the microstructure.

• Periodical: Materials Science Forum (Volume 879)
• Pages: 732-737
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.879.732
• Online since: November 2016
• Authors: Anita Heczel*, Lola Lilensten, Julie Bourgon, Loic Perrière, Jean Philippe Couzine, Ivan Guillot, Guy Dirras, Yi Huang, Terence G. Langdon, Jenő Gubicza
• Keywords: High Entropy Alloys (HEAs), High-Pressure Torsion, Phase Transformation, X-Ray Diffraction

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