【摘要】 采用机械合金化（MA）和热等静压（HIP）工艺制备了不同Y₂O₃含量的9Cr ODS钢。采用同步辐射小角X射线散射（SAXS）、高分辨透射电镜（HRTEM）和X射线吸收精细结构（XAFS）光谱研究了Y₂O₃含量对9Cr ODS钢中形成的纳米氧化物的数量密度、结构和尺寸分布的影响。同时测定了不同Y₂O₃含量的9Cr ODS钢在室温和高温下的拉伸性能。结果表明，三种9Cr ODS钢中均形成了焦绿石结构Y₂Ti₂O₇,当Y₂O₃含量为0.3%（质量分数）时，Y-Ti-O纳米团簇的数密度最高，达到1.39×10²⁴m^-3。当Y₂O₃含量为0.7%（质量分数）时，Y₂Ti₂O₇或Y₂O₃的数密度大于其他两种样品。0.7Y样品的XAFS结果与Y₂O₃参考样品接近。0.3Y样品的晶粒尺寸比其他两个样品大。Y₂O₃含量为0.3%（质量分数）的9Cr ODS钢比Y₂O₃含量为0.1%（质量分数）和0.7%（质量分数）的9Cr ODS钢具有更高的抗拉强度和更高的塑性。更多还原

【Abstract】 9Cr-ODS steels with different Y₂O₃ contents were produced by mechanical alloying（MA） and hot isostatic pressing（HIP）. The effects of Y₂O₃ contents on number density, structure and size distribution of nano-scale oxides formed in the 9Cr-ODS steels were investigated by synchrotron radiation small angle X-ray scattering（SAXS）, high resolution transmission electron microscope（HRTEM） and X-ray absorption fine structure（XAFS） spectrum. The tensile properties of the 9Cr-ODS steels with different Y₂O₃ contents at room temperature and elevated temperatures were also measured at the same time. The results showed that pyrochlore structure Y₂Ti₂O₇ is formed in three 9Cr-ODS steels, when Y₂O₃ content was 0.3wt% the number density of Y-Ti-O nano-clusters was highest(1.39×10²⁴ m^-3). While the number density Y₂Ti₂O₇ or Y₂O₃ was more than other two samples if the Y₂O₃ content was 0.7%（mass%）. The XAFS result of 0.7Y sample was closed to Y₂O₃ reference sample. The sample of 0.3Y had bigger grain size than other two samples. The 9Cr-ODS steels with Y₂O₃ content of 0.3wt% exhibited the higher tensile strength together with higher ductility than the 9Cr-ODS steels with Y₂O₃ contents of 0.1wt% and 0.7wt%.更多还原