酸化物分散強化鋼の高温照射環境下における強度劣化とその機構の解明

高温辐照环境下氧化物弥散强化钢的强度劣化及其机理阐明

• 批准号: 14F04903
• 负责人: 佐藤 裕樹
• 金额: $ 1.47万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for JSPS Fellows
• 财政年份: 2014
• 资助国家: 日本
• 起止时间: 2014-04-25 至 2017-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14F04903/
• 关键词: 原子力材料; 酸化物分散強化鋼; クリープ強度; 微細組織変化; ヘリウム注入; 高温熱処理; ナノ粒子; nuclear materials; oxide dispersion; creep properties; irradiation effect; thermal stability; microstructure; nano-scale particles; ODS steels; 原子力材料; 酸化物分散強化鋼; クリープ強度; 微細組織変化; ヘリウム注入; 高温熱処理; ナノ粒子; nuclear materials; oxide dispersion; creep properties; irradiation effect; thermal stability; microstructure; nano-scale particles; ODS steels

We studied microstructural evolution and mechanical properties change of an oxide dispersion strengthened steel (12Cr-ODS) for nuclear application.The effect of high-temperature annealing at 1473-1673 K on the coarsening kinetics of nanoparticles and microstructural evolution was systematically investigated. The nanoparticles were extremely stable and continued precipitating during annealing at 1473 K, whereas, significant coarsening took place during exposure at 1673 K. Furthermore, heterogeneously distributed voids were developed, sizes of which increased distinctly at 1573 and 1673 K for longer holding time. This is probably due to the growth and/or aggregation of Ar-entrapped and pre-existed voids in the as-fabricated condition. Additionally, no obvious changes were observed in texture at 1473 K, except that its intensity reduced. The hardness slightly decreased at 1473 K up to 24 h, however, obvious reduction was observed after annealing at 1573 and 1673 K for more than 6 h.The helium implantation experiments were carried out in cyclotron accelerator in Tohoku University. The implanted helium reached 390 μm from the surface, and concentration was 35 and 70 appm. The creep properties were tested at 873 and 973 K with different stresses. The helium leaded to slight reduction in creep time-to-rupture and strain-to-rupture at 973 K. While it shows almost no effects at 873 k. It indicates that 12Cr-ODS steel has the good resistance to helium irradiation, which was derived from the high number density and dispersed nano-particles.

我们研究了氧化物分散剂加强钢（12CR-ODS）的微观结构进化和机械性能的变化。高温退火在1473-1673 K上对纳米颗粒和微观结构进化的粗化动力学的影响进行了系统的研究。纳米颗粒非常稳定，在1473 K的退火过程中持续沉淀，而在1673 K暴露期间发生了明显的变形。此外，开发了异质分布的空隙，尺寸在1573和1673 k时大大增加，较长的固定时间。这可能是由于在拟合条件下的Ar填充和预先存在的空隙的生长和/或聚集。此外，在1473 K处的纹理中未观察到明显的变化，除了其强度降低。在1473 K到24小时的1473 K时，硬度略有下降，但是，在1573和1673 K退火后观察到明显的减少，持续了6小时以上。氦植入实验是在Tohoku大学的回旋加速器中进行的。植入的氦气从表面达到390μm，浓度为35和70 APPM。在873 K和973 K下测试了蠕变特性，其应力不同。氦气导致蠕变到973 K处的蠕变时间破裂和应变到破裂。虽然在873 K时几乎没有影响。这表明12CR-ods钢具有良好的抗氦照射能力，氦辐射是源自高数量密度和分散的纳米粒子的。