Microstructural investigation of plastically deformed Ti{sub 20}Zr{sub 20}Hf{sub 20}Nb{sub 20}Ta{sub 20} high entropy alloy by X-ray diffraction and transmission electron microscopy

Journal Article · Thu Oct 15 00:00:00 EDT 2015 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2015.08.007· OSTI ID:22587028

Gubicza, J.; Heczel, A. ^[1]; Lilensten, L.; Couzinié, J. -P.; Perrière, L.; Guillot, I. ^[2]; Hocini, A. ^[3]

---

1. Department of Materials Physics, Eötvös Loránd University, Budapest, P.O. Box 32, H-1518 (Hungary)
2. Université Paris Est, ICMPE (UMR 7182), CNRS, UPEC, 94320 Thiais (France)
3. Université Paris 13, Sorbonne Paris Cité, LSPM (UPR 3407) CNRS, 99 avenue JB Clément, 93430 Villetaneuse (France)

The microstructure evolution in body-centered cubic (bcc) Ti{sub 20}Zr{sub 20}Hf{sub 20}Nb{sub 20}Ta{sub 20} high entropy alloy during quasi-static compression test was studied by X-ray line profile analysis (XLPA) and transmission electron microscopy (TEM). The average lattice constant and other important parameters of the microstructure such as the mean crystallite size, the dislocation density and the edge/screw character of dislocations were determined by XLPA. The elastic anisotropy factor required for XLPA procedure was determined by nanoindentation. XLPA shows that the crystallite size decreased while the dislocation density increased with strain during compression, and their values reached about 39 nm and 15 × 10{sup 14} m{sup −2}, respectively, at a plastic strain of ~ 20%. It was revealed that with increasing strain the dislocation character became more screw. This can be explained by the reduced mobility of screw dislocations compared to edge dislocations in bcc structures. These observations are in line with TEM investigations. The development of dislocation density during compression was related to the yield strength evolution. - Highlights: • Ti{sub 20}Zr{sub 20}Hf{sub 20}Nb{sub 20}Ta{sub 20} high entropy alloy was processed by arc-melting. • The mechanical was evaluated by RT compression test. • The microstructure evolution was studied by XLPA and TEM. • With increasing strain the dislocation character became more screw. • The yield strength was related to the development of the dislocation density.

• OSTI ID: 22587028
• Journal Information: Materials Characterization, Vol. 108; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 1044-5803
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
ALLOYS
ANISOTROPY
BCC LATTICES
COMPARATIVE EVALUATIONS
COMPRESSION
EDGE DISLOCATIONS
ENTROPY
FASTENERS
LATTICE PARAMETERS
MELTING
MICROSTRUCTURE
SCREW DISLOCATIONS
STRAINS
TRANSMISSION
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION
YIELD STRENGTH