抄録
The present work deals with a preferential grain growth process in a localized region utilizing local heating method in order to fabricate some unique microstructures different from those fabricated in the homogeneous way of microstructure evolution. A Monte Carlo simulation of grain growth under a heterogeneous temperature gradient, i.e. spot heating, was performed. Steep temperature gradient brought about a preferential grain growth in the higher temperature region, showing that the local heating was effective for the control of grain structure of polycrystalline materials. Such type of preferential grain growth became less significant under the mild temperature gradient. Local heating of pure copper foil with 0.2mm in thickness utilizing laser beam was performed by changing the irradiation conditions. In the case of 200W for laser power and 18mm/s for sweep velocity, some grains were observed to have larger grain sizes than their surrounding grains, suggesting a possibility of preferential grain growth in the localized region.
