Thin-walled copper tubes are usually produced by multi-pass float-plug drawing deformation. In general, the annealing treatment subsequently is necessary to release the stored energy and adjusts the microstructure. In this study, an investigation on the evolution of annealing twins as well as textures in the thin-walled (Ф6 mm × 0.3 mm) copper tube underwent holding time-free heat treatment was reported. Electron backscattered diffraction analysis reveals that a large number of Σ3 boundaries (60° 〈111〉 twin relationship) are produced at the early stage of heat treatment, which is due to the lower boundary energy. With the recrystallization proceeding, the migration rate of grain boundaries decreases on account of the grain growth; meanwhile, the unique Σ9 boundaries (38.9° 〈110〉 relationship) are formed due to the interaction of the Σ3 boundaries. As a result, the number fractions of Σ3 boundaries and high-angle grain boundaries decrease rapidly. During the grain growth stage, a strong recrystallization texture was formed due to the fact that the grains of Goss orientation have a growth advantage over the others. As a result, the initial copper texture was transferred into the Goss texture in domination.

薄壁铜管通常通过多道浮球拔拔变形来生产。通常，随后必须进行退火处理以释放存储的能量并调节微结构。在这项研究中，对无壁热处理的薄壁（Ф6mm×0.3 mm）铜管中退火孪晶的演变以及织构进行了研究。电子背散射衍射分析表明，在热处理的早期阶段，由于较低的边界能，产生了大量的Σ3边界（60°<111>孪晶关系）。随着再结晶的进行，由于晶界的生长，晶界的迁移率降低。同时，由于Σ3边界的相互作用，形成了独特的Σ9边界（38.9°〈110〉关系）。结果，Σ3晶界和高角度晶界的数量分数迅速降低。在晶粒生长阶段，由于高斯取向晶粒比其他晶粒具有生长优势，因此形成了很强的再结晶织构。结果，最初的铜纹理被主导地转移到高斯纹理中。