Underlying data for: Damage Kinetics in High-Temperature Irradiated Ni Crystals

The set contains 3 folders (TEM, SEM, Nanoindentation) containing raw test results for a specific method.

→ SEM

In SEM folder there are three original SEM images used in Fig.1, namely: Fig.1a, Fig. 1b, Fig. 1c

Fig.1 SEM images captured before (a) and after (b) EG and (c) EP treatment as well as (d) RBS/C results obtained for pristine material before and after sample preparation (MP – mechanical polishing, EG – electron gun, EP – electro-polishing). Also shown in (d) is the aligned, pristine spectrum (orange solid line) as predicted by MC simulations in McChasy code (pristine MC sim.).

→ TEM

In TEM folder there are 2 sub-folders named “Fig.2” and “Fig. 3”. In sub-folder “Fig.2”  there are 3 original images that make up Fig.3 b,c and d. Below please find the description:

Fig. 2. TEM images of the Ni crystals bombarded with Ar ions to fluences of 7 × 10¹⁴, 7 × 10¹⁵, and 1 × 10¹⁶ cm⁻², denoted by Ni 7E14, Ni 7E15, and Ni 1E16, respectively: (a) cross-sectional images (orange curve represents the damage distribution profile obtained using SRIM), (b-d) bright-field images (red circles indicate dislocation loops), corresponding defect densities (e) and defect sizes (f), calculated based on the TEM images taken at the damage peak region.

Based on these 3 images, the calculations in Fig. 2 e and Fig. 2 f can be made.

Another sub-folder named “Fig. 3” consist of 2 original files “Fig 3 a Ni7e15” and “Fig 3 b Ni1e16”. Based on these images it is possible to calculate defect size and density (Fig.3 c and d). Below please find the description:

Fig. 3. (a-b) Bright-field images of bubbles in Ni bombarded samples with the fluences of 7 × 10¹⁵ cm⁻² and 1 × 10¹⁶ cm⁻², denoted by Ni 7E15 and Ni 1E16 respectively, (c) Ar bubble density, and (d) average bubble size.

→ Nanoindentation

In “Nanoindentation” folder there are three .txt files, which make up Fig.4: first “AR Ni_1e16 0,1-6 mN”, second “AR Ni_7e14 0,1-6 mN”, and third “AR Ni_7e15 0,1-6 mN”

Fig.4. Nanoindentation hardness of Ni samples irradiated up to the fluence of 1 × 10¹⁶ cm⁻².

→ Simulations

MC/MD

“The virtual Ni structures were created using ATOMSK software [30] and then they were transferred to MD-based LAMMPS code for further processing. Interactions between atoms were approximated by the Embedded Atom Model (EAM) potential with parameters given by Foiles [31]. To avoid surface effects, simulations were performed under periodic boundary conditions. Temperature and pressure were controlled by Nosé–Hoover algorithm [32].”

“MC simulations were performed using the most recent versions of two simultaneously developed versions of the McChasy software, namely McChasy-1 v.65 and McChasy-2 v.2.2. In McChasy-1 [33], [34], [35], the structures are created by internal software based on crystallographic data. Thermal vibrations and desired defects are applied from built-in procedures during ongoing simulations. In McChasy-2, the structures are generated using an open-source Large-scale Atomic/Molecular Massively Parallel Simulator Molecular Dynamic code (LAMMPS) [36]. The potential of early versions of the code has already been presented elsewhere [37], [38], [39].

The model of edge dislocations and dislocation loops developed for McChasy-1 is based on the Peierls-Nabarro approach [40], [41], [42] and requires geometrical parameters of the defect to be determined for every structure independently [9], [35], [43]. To have a possibility to compare the results with part of the results previously obtained for single-phase concentrated solid-solution alloys (SP-CSAs), in this study we used the mixture of 〈1 0 0〉 and 〈0 1 0〉 -oriented edge dislocations (same as in Ref. [8]).”

→ RBS/C_MSDA

“To reveal the damage kinetics for the investigated structure, the Multi-Step Damage Accumulation (MSDA) analysis was performed [38], [47]. This model is based on the equation assuming that the damage accumulation occurs through a series of structural transformations caused by the destabilization of the present crystal structure”: 

f_d = sum_{i=1}^{n}(f_{d,i}^{sat}-f_{d, i-1}^{sat})G[1-exp(sigma_{i}(Phi - Phi_{i-1}))]                     (2)

where:

sigma_i - cross-section for the formation of a given kind of defect

    f_{d,i}^{sat} -  level of damage at saturation for i-th kind of defects

Phi_i - fluence threshold for triggering the formation of i-th kind of defects “

“Financial support from the National Science Centre, Poland through the PRELUDIUM 21 program in the frame of grant no. 2022/45/N/ST5/02980 is gratefully acknowledged.”