Abstract Oxide dispersion strengthened (ODS) steels exhibit superior mechanical properties and irradiation resistance due to nano-sized oxides, highly dispersed in the metallic matrix. The mechanical properties are affected by the structure, composition, size and density of the nano-sized oxides. Despite numerous reports on the characterization of these oxides, ambiguity regarding their composition, crystallographic structure and orientation relationship with the matrix remains. In the present study, characterization of the crystallographic structure of oxide particles existing in 14%Cr ODS steel was performed using classical and novel transmission electron microscopy (TEM) methods. 3D dispersion, density and composition of these oxides were evaluated by atom probe tomography (APT). Three populations of particles were detected: highly dispersed, 3–20 nm Fe(Cr,Ti,Y)O particles with spinel structure; 50–150 nm YTiO3 and large (100–200 nm) particles identified as cubic TiC. The spinel-type particles displayed Bain and Kurdjumov-Sachs orientation relationships (OR) with the ferritic matrix. Applying electron diffraction tomography, the YTiO3 structure was attributed to the GdFeO3 (distorted perovskite)-type and its lattice parameters were refined as a = 5.46 A, b = 7.66 A and c = 5.28 A. Orientation relationship of the YTiO3 particles and Fe matrix were determined as [110]Fe//[210]oxide and (110)Fe//(002)oxide.

中文翻译：

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使用经典和前沿显微镜方法表征 14% Cr 氧化物弥散强化 (ODS) 钢中的纳米颗粒

摘要 氧化物弥散强化 (ODS) 钢由于纳米级氧化物高度分散在金属基体中而表现出优异的机械性能和抗辐照性。机械性能受纳米级氧化物的结构、组成、尺寸和密度影响。尽管有大量关于这些氧化物表征的报告，但关于它们的成分、晶体结构和与基体的取向关系的模糊性仍然存在。在本研究中，使用经典和新型透射电子显微镜 (TEM) 方法对 14% Cr ODS 钢中存在的氧化物颗粒的晶体结构进行表征。这些氧化物的 3D 分散、密度和成分通过原子探针断层扫描 (APT) 进行评估。检测到三种粒子群：高度分散、3-20 nm Fe(Cr,Ti,Y)O 颗粒，具有尖晶石结构；50–150 nm YTiO3 和大 (100–200 nm) 颗粒被确定为立方 TiC。尖晶石型颗粒显示出与铁素体基体的贝恩和库尔德朱莫夫-萨克斯取向关系 (OR)。应用电子衍射断层扫描，YTiO3 结构归因于 GdFeO3（畸变钙钛矿）型，其晶格参数细化为 a = 5.46 A、b = 7.66 A 和 c = 5.28 A。 YTiO3 颗粒和 Fe 基体的取向关系测定为[110]Fe//[210]氧化物和(110)Fe//(002)氧化物。