KWN model with external deformation considered via the amount of excess vacancies

KWN precipitation model including the effect of deformation via excess vacancy concentration calculation (phenomenological law for vacancy production).

The model is described in detail in reference [3].

Requirements

Compiler: gfortran or ifort

Installer: Fortran Package Manager. If using on MacOS, please install with Conda Package Manager and not with homebrew.

Installing the program

Building with fpm

The FPM settings are defined in the file fpm.toml. The instructions for building and testing KWN-deform are listed below.

Tests are run using the Test Drive package, as listed in the [dev-dependencies] section of the fpm.toml file. This requires the -DWITH_QP=1 flag to be included in FPM_FFLAGS; if you are not running the tests this flag can be left out.

Building should be done either gfortran or intel, and the instructions are below

Building with gfortran

Compilation with gfortran versions 6.4.0 to 11.3.0 has been tested, and the following options will create optimised binaries:

export FPM_FC=gfortran
export FPM_FFLAGS="-fbounds-check -ffree-line-length-0 -fimplicit-none -O3 -DWITH_QP=1"
fpm build
fpm test

Building with intel

Compilation with intel versions 17.0.7 to 19.1.2 have been tested, and the following options will create optimised binaries:

export FPM_FC=ifort
export FPM_FFLAGS="-traceback -check all -O3 -DWITH_QP=1"
fpm build
fpm test

Installing with fpm

The model can be installed using the fpm install command. This will install the binary and libraries (in bin and lib/include respectively). For a standard user these will be installed with the root ~/.local/, but to change this root you can use the --prefix flag:

fpm install --prefix <prefix directory>

Depending on the shell you are using, you might need to add the KWN-Deform code to the path. To know which shell you are using, please run the following command:

echo $SHELL

If it's BASH you do not need to do anything. If it is ZSH, please open the ./run_kwn.sh file and replace line LOC_KWN=which 'KWN-Deform' by LOC_WKN='<loc>/KWN-Deform' where <loc> is ~/.local/bin for standard user or whatever <prefix directory> you used if you chose this option.

Running the Model

1. Create, or modify, your simulation folder (test_folder) in the tests directory
2. Inside your test_folder, create, or modify an existing, namelist.input file with input corresponding to the model described in ref. [3]. Information on the settings for the namelist is given in the README_namelist.txt help file.
3. Create a results folder within the test_folder.
4. Go to tests directory in a terminal and run the following command:

   ./run_kwn.sh test_folder 
   

5. The outputs are written in textfiles within the output folder defined above, and example Jupyter notebooks containing code for visualising these are included in the tests folders.

Some examples of input files and jupyer notebooks can be found in the tests directory:

• tests/test_1:
  • with deformation in a ternary alloy (Al-Zn-Mg) containing an initial distribution
• tests/test_2:
  • without deformation in a binary alloy with no initial distribution, for a Cu-Co binary alloy (reproduces result of ref [7]).

Short copies of these examples (test_1a and test_2a) can be run using the run_basic_test.sh script within the tests directory.

Note : a bash script has been added to run the model more easily. It is located in the tests folder. To use it, you just need to go to the tests folder and then run ./run_kwn.sh testfolder in a terminal (where testfolder contains a results directory and the namelist.input file as stated above.)

Modifying the Model

The model can be modified or features can be added by modifying the files in the src directory. Once the changes have been made, first refer to the sections "building with gfortran" or "building with Intel" above.

Then the program should be recompiled by running the following commands in a command line:

conda activate fpm
fpm clean
fpm build
fpm install

Authors

Madeleine Bignon, University of Manchester
Pratheek Shanthraj, University of Manchester
Samuel Engel, University of Manchester

Copyright & Licensing

This software has been developed as part of the Lightform project at the University of Manchester.

• Copyright 2023 University of Manchester

Licensed under the MIT license, see the file License.md for details.

References

[1] Robson, J. D. (2020). Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, 51(10), 5401–5413. https://doi.org/10.1007/s11661-020-05960-5
[2] Deschamps, A., Livet, F., & Bréchet, Y. (1998). . Acta Materialia, 47(1), 281–292. https://doi.org/10.1016/S1359-6454(98)00293-6
[3] Bignon, M., Shanthraj, P., & Robson, J. D. (2022). Acta Materialia, 234, 118036. https://doi.org/10.1016/J.ACTAMAT.2022.118036
[4] Deschamps, A., & De Geuser, F. (2011). Journal of Applied Crystallography, 44(2), 343–352. https://doi.org/10.1107/S0021889811003049
[5] Perez, M. (2005). Scripta Materialia, 52(8), 709–712. https://doi.org/10.1016/j.scriptamat.2004.12.026
[6] Nicolas, M., & Deschamps, A. (2003). Acta Materialia, 51(20), 6077–6094. https://doi.org/10.1016/S1359-6454(03)00429-4
[7] Robson, J. D. (2004). Modelling the evolution of particle size distribution during nucleation, growth and coarsening. Materials Science and Technology, 20(4), 441–448. https://doi.org/10.1179/026708304225016725