Zr alloys are used as cladding materials in nuclear reactor, and new alloys and process are continuously developing. This work focuses on the influence of loading direction on deformation and subsequent annealing behavior of hexagonal Zr-4 alloy. As-received Zr-4 sheets with recrystallized microstructure and strong crystallographic texture were compressed along the normal direction (ND) and rolling direction (RD) at room temperature. Different strain levels were applied and subsequent annealing at various temperatures was carried out. Microstructures and textures were characterized by electron backscatter diffraction (EBSD) method. For a same strain level, the fraction of low angle misorientation is higher after ND compression than RD compression, indicating higher stored dislocation density. During annealing, obvious recrystallization causes grain growth in ND compressed specimens when the annealing temperature is higher than 650 °C, while no significant recrystallization happens in RD compressed specimens, even annealed at 700 °C. Visco-plastic self-consistent (VPSC) simulations are used to evaluate the type of stored dislocations, their density and the stored energy, and explain the different annealing behaviors after ND compression and RD compression.

Zr合金被用作核反应堆的包层材料，并且新合金和新工艺正在不断发展。这项工作的重点是载荷方向对六方Zr-4合金的变形和随后的退火行为的影响。在室温下，将具有再结晶组织和强晶体织构的Zr-4片材沿法线方向（ND）和轧制方向（RD）压缩。施加不同的应变水平，然后在各种温度下进行退火。通过电子背散射衍射（EBSD）方法对微结构和织构进行了表征。对于相同的应变水平，ND压缩后的低角度取向差分数要高于RD压缩，这表明较高的存储位错密度。在退火过程中，当退火温度高于650°C时，明显的再结晶会导致ND压缩样品中的晶粒生长，而RD压缩样品中甚至在700°C的退火温度下都不会发生明显的再结晶。粘塑性自洽（VPSC）模拟用于评估存储的位错的类型，密度和存储的能量，并解释ND压缩和RD压缩后的不同退火行为。