抄録
The solidification texture of weld metal was investigated for laser irradiated aluminum. Both cold rolled and recrystallized specimens of 1.2 mm thickness were irradiated using a 1.2 kW CO2 laser, at three different welding speeds; 41.7, 62.5 and 83.3 mm/s. The following results were obtained. (1) The main components of the solidification texture, both for the cold rolled and for the recrystallized specimens are (001) [100] and {112}⟨111⟩-{123}⟨634⟩, which is almost the same as the usual recrystallization texture for cold rolled aluminum. These are independent of welding speeds. (2) In the recrystallized specimens, the columnar grains in the bead grow from matrix grains adjacent to the fusion boundary by keeping the same orientation as if matrix grains are seed crystals. (3) In the cold rolled specimens, recrystallized grains in the heat affected zone due to laser irradiation act as the seed crystals for the growth of the columnar grains in the beads.
