研究了1150℃时效时Ti-48Al合金全片层组织的连续粗化机制。片层组织的连续粗化不仅能通过片层界面缺陷(如台阶、端部、弯曲的界面等)迁移来实现，而且可以通过γ/γ片层界面迁移或分解的方式来实现；在真孪晶、伪孪晶和120°旋转有序型γ/γ界面当中，120°旋转有序界面的稳定性最低，最容易迁移或分解；γ片层内的120°旋转有序畴界与片层界面的交汇处易形成热沟(thermal groove)，它往往成为片层界面发生分解的起始部位。
The continuous coarsening mechanism of the fully lamellar microstructure of Ti-48Al alloy aged at 1150℃ was studied by TEM. The continuous lamellar coarsening could be occurred not only by the interface faults (such as: ledges, edges and curved interfaces) migrating, but also by the migration and dissolution of γ/γ lamellar interfaces. Among the true-twin, pseudo-twin and 120°-rotational ordered types γ/γ lamellar interfaces, the thermal stability of the 120°-rotational ordered interface was the lowest, it was migrated or dissolved frequently. The thermal grooves were often formed at the triple point junctions between the 120°-rotational ordered domain boundaries in γ lamella and the lamellar interfaces, which was the original dissloution position of the lamellar interfaces.
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