FRACTAL GRAIN-BOUNDARIES IN GROWTH COMPETITION

Evidence of fractal grain boundaries is found in polycrystals when rad ial patterns are found to result from a geometrical competition betwee n different grains that have nucleated on the same center. A simple st atistical model presented herein predicts the universal fractal dimens ion 2.33 of such natural patterns grown through internal competition. The application to material patterns having constrained front propagat ion involving many components is obvious.