Open AccessINDENTATION SIZE EFFECT IN HIGH PRESSURE TORSION PROCESSED HIGH ENTROPY ALLOY
Author(s) -
Petr Haušild,
Jakub Čı́žek,
Jaroslav Čech,
Jiří Zýka,
Hyoung Seop Kim
Publication year - 2020
Publication title -
acta polytechnica ctu proceedings
Language(s) - English
Resource type - Journals
ISSN - 2336-5382
DOI - 10.14311/app.2020.27.0141
Subject(s) - indentation , materials science , torsion (gastropod) , nanoindentation , alloy , grain size , high entropy alloys , composite material , hardening (computing) , indentation hardness , high pressure , severe plastic deformation , metallurgy , mechanics , microstructure , medicine , physics , surgery , layer (electronics)
High entropy alloy HfNbTaTiZr in as cast conditions and after high pressure torsion straining was characterized by nanoindentation. The length-scale dependent material response (indentation size effect) was characterized by indentation at various indentation depths. Hardness dependence on the characteristic length (depth of penetration) indicated decomposition of disordered high entropy alloy in the as cast sample, which probably occurred during slow cooling after casting. Subsequent severe plastic deformation by high pressure torsion led on the other hand to the short-range disorder of (originally partially decomposed as cast) structure. Further hardening was generated during high pressure torsion by the mechanisms of grain refinement and increasing dislocation density.