Shoaib Mehboob , Hyun Joon Eom, Chaewon Jeong, Changheui Jang
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引用次数: 0
Abstract
Long-term operation of cast austenitic stainless steels (CASSs) at high temperatures in nuclear power plants results in embrittlement due to δ-ferrite hardening from nanoscale precipitates, with Mo addition further accelerating the embrittlement through enhanced spinodal decomposition and G-phase precipitation. Meanwhile, the formation of distinct Mo-rich precipitates in δ-ferrite during thermal aging are occasionally reported, but they were not clearly characterized. Here, we characterized the Mo-rich precipitates in δ-ferrite formed during thermal aging at 400 °C using high-resolution TEM images and electron diffraction patterns. Based on the detailed analysis, the Mo-rich precipitates were identified as hexagonal ω-phase.
在核电站中,铸造奥氏体不锈钢(CASS)在高温下长期运行会因纳米级析出物导致δ-铁素体硬化而脆化,而钼的添加会通过增强旋光分解和 G 相析出进一步加速脆化。同时,偶尔也有报道称δ-铁氧体在热老化过程中会形成明显的富钼沉淀,但其特征并不明确。在此,我们利用高分辨率 TEM 图像和电子衍射图谱对 400 °C 热老化过程中在δ-铁氧体中形成的富钼沉淀进行了表征。根据详细分析,富钼析出物被确定为六方ω相。
期刊介绍:
The Journal of Nuclear Materials publishes high quality papers in materials research for nuclear applications, primarily fission reactors, fusion reactors, and similar environments including radiation areas of charged particle accelerators. Both original research and critical review papers covering experimental, theoretical, and computational aspects of either fundamental or applied nature are welcome.
The breadth of the field is such that a wide range of processes and properties in the field of materials science and engineering is of interest to the readership, spanning atom-scale processes, microstructures, thermodynamics, mechanical properties, physical properties, and corrosion, for example.
Topics covered by JNM
Fission reactor materials, including fuels, cladding, core structures, pressure vessels, coolant interactions with materials, moderator and control components, fission product behavior.
Materials aspects of the entire fuel cycle.
Materials aspects of the actinides and their compounds.
Performance of nuclear waste materials; materials aspects of the immobilization of wastes.
Fusion reactor materials, including first walls, blankets, insulators and magnets.
Neutron and charged particle radiation effects in materials, including defects, transmutations, microstructures, phase changes and macroscopic properties.
Interaction of plasmas, ion beams, electron beams and electromagnetic radiation with materials relevant to nuclear systems.