スエージング加工した純アルミニウムおよびAl-2%Fe合金P/M材の再結晶集合組織に及ぼすレーザ照射の影響 Effects of irradiation on recrystallization textures of swaged pure aluminum and Al-2%Fe P/M alloy
A laser shot local melting technique was applied as an artificial nucleation process. Pure aluminum processed through ingot metallurgy and an Al–2%Fe powder metallurgy alloy were cold swaged. The surface layer of specimen cut from the swaged bar parallel or perpendicular to the swaging direction (SD) was melted by one by one shots of laser and then the specimens were annealed. In pure Al shot parallel to SD,  oriented grains pre-existing in the unmelted matrix grow continuously by re-solidification and grow back into the matrix by recrystallization, developing a strong  recrystallization texture. While this is not the case for pure Al shot perpendicular to SD. In Al–2Fe shot parallel to SD, a  solidification texture seems to develop not by growth of matrix grains but by independent nucleation. The re-solidified grains do not grow by recrystallization, leading to the formation of the previously reported  texture in the matrix. It is argued that the anisotropic growth behavior of  re-solidified grains by recrystallization in pure aluminum may stem from structural characteristics of its deformed matrix, while in the PM alloy compound particles suppress both growth of pre-existing grains by re-solidification and growth of re-solidified grains by recrystallization.
軽金属 46(5), 231-236, 1996-05-30
The Japan Institute of Light Metals