A hardening model considering grain size effect for ion-irradiated polycrystals under nanoindentation

Autor: Kai Liu, Xiangyun Long, Bochuan Li, Xiazi Xiao, Chao Jiang
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Nuclear Engineering and Technology, Vol 53, Iss 9, Pp 2960-2967 (2021)
Druh dokumentu: article
ISSN: 1738-5733
DOI: 10.1016/j.net.2021.03.007
Popis: In this work, a new hardening model is proposed for the depth-dependent hardness of ion-irradiated polycrystals with obvious grain size effect. Dominant hardening mechanisms are addressed in the model, including the contribution of dislocations, irradiation-induced defects and grain boundaries. Two versions of the hardening model are compared, including the linear and square superposition models. A succinct parameter calibration method is modified to parametrize the models based on experimentally obtained hardness vs. indentation depth curves. It is noticed that both models can well characterize the experimental data of unirradiated polycrystals; whereas, the square superposition model performs better for ion-irradiated materials, therefore, the square superposition model is recommended. In addition, the new model separates the grain size effect from the dislocation hardening contribution, which makes the physical meaning of fitted parameters more rational when compared with existing hardness analysis models.
Databáze: Directory of Open Access Journals