TY - JOUR
T1 - Mechanisms of structural evolution of laminates with immiscible components under high-pressure torsion
AU - Mazilkin, A.
AU - Tavakkoli, V.
AU - Davydenko, O.
AU - Beygelzimer, Y.
AU - Boltynjuk, E.
AU - Boll, T.
AU - Straumal, B.
AU - Baretzky, B.
AU - Estrin, Y.
AU - Kulagin, R.
N1 - Funding Information:
This research was performed as part of the Helmholtz Joint Laboratory Model Driven Materials Characterization (MDMC). The authors gratefully acknowledge funding of this study received from the Volkswagen Foundation through the Cooperation Project Az.: 97 751. Partial support from the Karlsruhe Nano Micro Facility (KNMFi, https://www.knmf.kit.edu), a Helmholtz Research Infrastructure at Karlsruhe Institute of Technology (KIT, www.kit.edu, proposal #2022-029-031547) is also acknowledged. The purchase of KLA nanoindenter iNano was enabled by 3DMM2O - Cluster of Excellence (EXC-2082/1 – 390761711).
Funding Information:
This research was performed as part of the Helmholtz Joint Laboratory Model Driven Materials Characterization (MDMC). The authors gratefully acknowledge funding of this study received from the Volkswagen Foundation through the Cooperation Project Az.: 97 751. Partial support from the Karlsruhe Nano Micro Facility (KNMFi, https://www.knmf.kit.edu ), a Helmholtz Research Infrastructure at Karlsruhe Institute of Technology (KIT, www.kit.edu , proposal #2022-029-031547) is also acknowledged. The purchase of KLA nanoindenter iNano was enabled by 3DMM2O - Cluster of Excellence (EXC-2082/1 – 390761711).
Publisher Copyright:
© 2024 The Author(s)
PY - 2024/5/1
Y1 - 2024/5/1
N2 - The mechanism of structural evolution of a three-layer Cu-Mo-Cu laminate under high-pressure torsion (HPT) was studied using scanning and transmission electron microscopy, atom probe tomography, and nanoindentation, complemented with finite element calculations. The results demonstrate a gradual refinement of the structure of the Mo component; a greater degree of refinement is observed in the peripheral part of the disk-shaped HPT specimen, although some heterogeneity of the structure remains even at a gigantic degree of shear deformation accumulated therein. The elemental distribution calculated from STEM-EDX mapping as well as 3D reconstruction of atom probe tomography results shows a significant degree of mixing of the sample components at the atomic level, the concentration of copper in molybdenum and molybdenum in copper reaching ∼4.3 at.% and ∼6 at.%., respectively. These observations correlate with nanoindentation results showing an increase in the hardness of both phases due to strain hardening and solid solution strengthening, as well as grain refinement. Numerical simulations made it possible to provide a detailed description of the stages of the structure fragmentation, including its self-organizing nature, to show the formation of rupture forerunners in the hard Mo layer, and the deformation of harder fragments in a softer matrix. The experimental results are supported by a model assuming a fractal self-organization of a self-similar structure during HPT processing.
AB - The mechanism of structural evolution of a three-layer Cu-Mo-Cu laminate under high-pressure torsion (HPT) was studied using scanning and transmission electron microscopy, atom probe tomography, and nanoindentation, complemented with finite element calculations. The results demonstrate a gradual refinement of the structure of the Mo component; a greater degree of refinement is observed in the peripheral part of the disk-shaped HPT specimen, although some heterogeneity of the structure remains even at a gigantic degree of shear deformation accumulated therein. The elemental distribution calculated from STEM-EDX mapping as well as 3D reconstruction of atom probe tomography results shows a significant degree of mixing of the sample components at the atomic level, the concentration of copper in molybdenum and molybdenum in copper reaching ∼4.3 at.% and ∼6 at.%., respectively. These observations correlate with nanoindentation results showing an increase in the hardness of both phases due to strain hardening and solid solution strengthening, as well as grain refinement. Numerical simulations made it possible to provide a detailed description of the stages of the structure fragmentation, including its self-organizing nature, to show the formation of rupture forerunners in the hard Mo layer, and the deformation of harder fragments in a softer matrix. The experimental results are supported by a model assuming a fractal self-organization of a self-similar structure during HPT processing.
KW - Cu-Mo-Cu laminate
KW - Finite element method
KW - High-pressure torsion
KW - Mixing
KW - Self-similar structure
KW - Severe plastic deformation
KW - Turbulent flow
UR - http://www.scopus.com/inward/record.url?scp=85187193574&partnerID=8YFLogxK
U2 - 10.1016/j.actamat.2024.119804
DO - 10.1016/j.actamat.2024.119804
M3 - Article
AN - SCOPUS:85187193574
SN - 1359-6454
VL - 269
JO - Acta Materialia
JF - Acta Materialia
M1 - 119804
ER -