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Professor Yoshiyuki Saito
Waseda University
Department of Materials Science and Engineering
3-4-1 Okubo, Shinjuku-ku, Tokyo, 169 Japan
            yoshi@dice.cache.waseda.ac.jp
Simulation of grain growth kinetics using a Monte Carlo method in two dimensions. This is a new algorithm which has the advantage that it prevents grains of the same orientation from coalescing.
| Language: | FORTRAN | 
| Product form: | Source code | 
The program reads inputs from a file, in this case called Graingrowth.montecarlo.dat which contains the following: 256 256 200 1459873 32 2048 1.00 3 The first and second numbers specify the system size which is the number of cells in the two-dimensional Monte Carlo simulation. The third number is the time in Monte Carlo units. The fourth number is the initial random number which should be a prime number. The fifth number sets the total number of orientations of the grains in the simulation. The sixth number is the initial number of grains. The seventh number sets the anisotropy of the grain boundary energy (a value of unity represents isotropy, and values less than unity but greater than zero represent an orientation dependence of interface energy). The final number need not be altered at all; it is a file control parameter.
The Monte Carlo simulation method is now widely applied to materials science and engineering. This program deals with grain growth kinetics in two-dimensions, with the simulation of interface motion based on the Potts model. As an initial microstructure, an orientation between 1 to Q is assigned to each lattice site at random. The evolution of the grain structure then occurs during the Monte Carlo iterations. It is possible to obtain both the mean grain size and the grain size distribution.
These are read from the file Graingrowth.montecarlo.data which has a single row as follows :-
Output is to three ASCII files, fort.15, fort.16 and fort.17. See program results (below) for format.
None.
See [2], which has a comparison between calculations and experimental observations.
A three-dimensional simulation will be available in the near future.
       See full program
256 256 200 1459873 32 2048 1.00 3
There are three output files created, fort.15, fort.16 and fort.17
File fort.15 has two columns, the first representing the Monte Carlo time, and the second, the number of grains remaining :-
         1      1552
         2      1552
         3      1552
         4      1552
         5      1552
         6      1552
         7      1552
         8      1552
         9      1552
        10      1552
        11      1552
        12      1552
        13      1552
        14      1552
        15      1552
        16      1552
        17      1552
        18      1552
        19      1552
        20      1552
        21      1552
        22      1552
        23      1552
        24      1552
        25      1552
        26      1552
        27      1552
        28      1552
        29      1552
        30      1552
        31      1552
        32      1552
        33      1552
        34      1552
        35      1552
        36      1552
        37      1552
        38      1551
        39      1550
        40      1550
        41      1550
        42      1550
        43      1550
        44      1550
        45      1550
        46      1549
        47      1549
        48      1549
        49      1549
        50      1549
       100      1534
       150      1494
       200      1444
File fort.16 has columns which represent 10, 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000 Monte Carlo time steps. The number of columns may be less than 10 if the simulation is stopped at an earlier end point (less than 10000). Each row represents the fraction of grains which have the same number of corners as the row number (i.e., row 5 represents pentagons and row 10 decagons) :-
      0.00      0.00      0.06      0.00      0.21
      0.32      0.52      0.52      1.04      0.97
      3.35      3.93      3.74      4.17      4.57
     13.72     12.18     12.46     12.39     13.30
     21.78     21.46     21.37     20.66     19.88
     24.74     25.00     25.18     23.14     22.02
     18.04     19.78     18.27     18.64     17.80
     11.28     10.18     10.65     12.19     12.60
      4.64      4.96      5.81      5.08      5.61
      1.74      1.68      1.36      2.28      2.22
      0.32      0.19      0.52      0.33      0.69
      0.06      0.13      0.06      0.07      0.14
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
File fort.17 has columns which represent 10, 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000 Monte Carlo time steps. The number of columns may be less than 10 if the simulation is stopped at an earlier end point (less than 10000). Row number 11 in each case gives the fraction of grains of average size. Row number 21 gives the fraction of grains of twice the average size. The other rows can be interpreted on the same rationale.
      0.06      0.39      0.77      2.09      3.88
      0.90      1.68      2.13      2.41      3.19
      3.41      2.84      3.10      5.08      5.54
      4.57      5.28      5.42      4.63      3.88
      7.02      6.77      5.75      6.39      7.34
      8.63      8.63      9.62      7.69      5.75
      8.63      7.54      7.62      7.30      7.27
      6.57      7.35      7.68      6.19      5.47
      8.38      7.09      6.58      6.91      6.86
      7.22      8.38      6.58      5.87      5.40
      8.76      8.18      8.07      7.24      6.86
      5.35      4.77      5.62      5.61      5.26
      5.54      5.61      4.65      4.82      5.26
      5.35      5.28      4.13      4.24      3.05
      3.09      3.61      4.84      3.26      3.53
      3.80      3.74      3.36      4.11      3.12
      2.19      2.06      2.39      2.48      3.67
      2.00      1.87      1.87      2.35      2.49
      1.55      1.68      1.61      1.89      2.49
      1.29      1.48      1.87      1.89      1.66
      1.55      1.22      1.68      1.76      1.32
      0.84      1.03      0.65      1.04      1.66
      0.90      1.03      0.84      0.91      0.90
      0.77      0.71      0.90      0.78      0.90
      0.39      0.52      0.39      0.78      0.90
      0.26      0.26      0.58      0.72      0.42
      0.13      0.13      0.32      0.07      0.48
      0.13      0.26      0.19      0.46      0.14
      0.13      0.06      0.06      0.07      0.21
      0.06      0.19      0.13      0.13      0.14
      0.13      0.00      0.13      0.20      0.28
      0.06      0.00      0.06      0.13      0.14
      0.06      0.13      0.06      0.13      0.21
      0.00      0.00      0.06      0.07      0.00
      0.06      0.00      0.00      0.00      0.07
      0.06      0.13      0.13      0.13      0.07
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.07      0.07
      0.13      0.06      0.00      0.00      0.07
      0.00      0.06      0.06      0.00      0.00
      0.00      0.00      0.06      0.07      0.07
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.07      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
      0.00      0.00      0.00      0.00      0.00
None.
Monte Carlo Simulation Grain Growth Kinetics
MAP originated from a joint project of the National Physical Laboratory and the University of Cambridge.
MAP Website administration / map@msm.cam.ac.uk