抄録
The oriented precipitation formed during the stress-aging of Al-3%Cu alloy were investigated by means of the X-ray oscillating crystal method. The compressive stress along the [001] direction induced the preferential formation of G.P. zones and θ″ phases perpendicular to the [001] axis. The degree of the orientation is increased by lowering the quenching temperature, i.e. by lowering the nucleation rate. It indicates that the stress orienting effect is determined in the stage of nuclei-formation. The stress oriented G.P. zones and θ″ phases were grown to θ″ and θ′ phases respectively in the additional free-aging, and it was clarified that the orientation of G.P. zones and θ″ phases are handed down to θ″ and θ′ phases, respectively. The finding leads to the conclusion that G.P. zones, θ″ and θ′ phases transform in regular sequence.
