種々の初期集合組織を有するAZ31BおよびAZ80マグネシウム合金の高温平面ひずみ圧縮変形下での組織と集合組織の形成機構

抄録

The effects of pre-existent textures on the evolution behaviors of microstructure and texture at high-temperature plane strain compression deformation of AZ31B magnesium alloy have been studied. Deformation is conducted at 723 K with a strain rate of 5.0 × 10⁻² s⁻¹, up to −1.3 in true strain. When non-basal slip systems are the primary slip systems, {1120}<1010> texture develops. In this case, repeated change in microstructure and texture which was found in the previous work appeared with increasing strain. Namely, replacement of {1120}<1010> texture with {1010}<1120> texture and the reverse phenomenon occurs. While the {1120}<1010> oriented grains are small and with wavy shaped grain boundaries, the {1010}<1120> oriented grains are large and with rather straight grain boundaries. The mechanism of repeated change in microstructure and texture is discussed on the basis of preferential dynamic grain growth mechanism proposed by the authors.

Repeated change in microstructure and texture during high temperature plane strain compression deformation of AZ31B （a） before deformation, after deformation up to true strains of（b） −0.3,（c） −0.4,（d） −0.7,（e） −0.8 and（f） −1.0. The colors indicate the orientations of the compression plane. Mechanism of the changes is explained on the basis of preferential dynamic grain growth mechanism.