Investigation of Lattice Defects in a Plastically Deformed High-Entropy Alloy

Abstract:

The lattice defect structure developed during plastic deformation in a High-Entropy Alloy (HEA) with the composition of Ti₃₅Zr_27.5Hf_27.5Nb₅Ta₅ was investigated. The crystallite size as well as the density and types of dislocations in a disk processed by High-Pressure Torsion (HPT) were determined by X-ray profile line analysis (XLPA). Additional transmission electron microscopy (TEM) investigations were carried out to monitor the grain size evolution during deformation. It was found that the dislocation density in the HPT-processed sample was very high compared to conventional materials. In addition, in Ti₃₅Zr_27.5Hf_27.5Nb₅Ta₅ HEA the initial body-centered cubic structure transformed into a martensitic phase during HPT. The hardness of this HEA was investigated along the HPT-processed disk radius and correlated to the microstructure.

• Periodical: Materials Science Forum (Volume 885)
• Pages: 74-79
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.885.74
• Online since: February 2017
• Authors: Anita Heczel*, Yi Huang, Terence G. Langdon, Jenő Gubicza
• Keywords: Dislocation, High-Entropy Alloy, Phase Transformation, Plastic Deformation, X-Ray Diffraction

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