TY - JOUR

T1 - High temperature nanoindentation of iron

T2 - Experimental and computational study

AU - Khvan, T.

AU - Noels, L.

AU - Terentyev, D.

AU - Dencker, F.

AU - Stauffer, D.

AU - Hangen, U. D.

AU - Van Renterghem, W.

AU - Cheng, C.

AU - Zinovev, A.

N1 - Funding Information: This work has been carried out within the framework of the EUROfusion Consortium, funded by the European Union via the Euratom Research and Training Programme (Grant Agreement No 101052200 — EUROfusion). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Commission. Neither the European Union nor the European Commission can be held responsible for them.

PY - 2022/8/15

Y1 - 2022/8/15

N2 - Application of reduced activation ferritic/martensitic (RAFM) steels as the structural material in future fusion reactors requires the knowledge of their mechanical properties under relevant operational conditions i.e. temperatures and irradiation by fast neutrons. Execution of the neutron irradiation and post irradiation examination is expensive and lengthy, therefore experimental and computational solutions to ease the characterization of as-irradiated materials are in the scope of interests of nuclear materials scientific community. Moreover, ion irradiation is considered as one possible way to surrogate high flux neutron irradiation damage. The extraction of the mechanical properties after ion irradiation primarily relies on the nanoindentation techniques and its subsequent post-processing to extract engineering relevant information, although some innovative techniques such as compression micropillars and micro-tensile testing also exist. In this work, we have performed nanoindentation on BCC iron, as the basis material for ferritic steels, by using a new Bruker stage developed for high temperature operation. The obtained results were analyzed by means of crystal plasticity finite element method (CPFEM), whereas the constitutive laws of the material were derived and established by using tensile deformation data, thus providing an interconnection of material's behavior under compressive and tensile deformations. The microstructural features such as indentation pile-up formation or dislocation density evolution were obtained by using transmission and scanning electron microscopy, and were compared with the predictions derived by the developed CPFEM model. It is demonstrated that a good agreement between the CPFEM and experimental data set, including tensile and compressive loads as well as associated microstructural changes, is obtained at room temperature and elevated temperature tests.

AB - Application of reduced activation ferritic/martensitic (RAFM) steels as the structural material in future fusion reactors requires the knowledge of their mechanical properties under relevant operational conditions i.e. temperatures and irradiation by fast neutrons. Execution of the neutron irradiation and post irradiation examination is expensive and lengthy, therefore experimental and computational solutions to ease the characterization of as-irradiated materials are in the scope of interests of nuclear materials scientific community. Moreover, ion irradiation is considered as one possible way to surrogate high flux neutron irradiation damage. The extraction of the mechanical properties after ion irradiation primarily relies on the nanoindentation techniques and its subsequent post-processing to extract engineering relevant information, although some innovative techniques such as compression micropillars and micro-tensile testing also exist. In this work, we have performed nanoindentation on BCC iron, as the basis material for ferritic steels, by using a new Bruker stage developed for high temperature operation. The obtained results were analyzed by means of crystal plasticity finite element method (CPFEM), whereas the constitutive laws of the material were derived and established by using tensile deformation data, thus providing an interconnection of material's behavior under compressive and tensile deformations. The microstructural features such as indentation pile-up formation or dislocation density evolution were obtained by using transmission and scanning electron microscopy, and were compared with the predictions derived by the developed CPFEM model. It is demonstrated that a good agreement between the CPFEM and experimental data set, including tensile and compressive loads as well as associated microstructural changes, is obtained at room temperature and elevated temperature tests.

KW - CPFEM

KW - High temperature

KW - Iron

KW - Nanoindentation

UR - http://www.scopus.com/inward/record.url?scp=85131793438&partnerID=8YFLogxK

U2 - 10.1016/j.jnucmat.2022.153815

DO - 10.1016/j.jnucmat.2022.153815

M3 - Article

AN - SCOPUS:85131793438

VL - 567

JO - Journal of nuclear materials

JF - Journal of nuclear materials

SN - 0022-3115

M1 - 153815

ER -