The augmentation of mechanical properties of reduced activation ferritic martensitic steels through the introduction of creep resistant nano-oxide particles produces a class of oxide dispersion strengthened steels, which have attracted significant interest as candidates for first wall supporting structural materials in future nuclear fusion reactors. In the present work, the effect of temperature on the elastic properties and micro-mechanics of 0.3 wt% YO oxide dispersion strengthened steel EUROFER97 is investigated using synchrotron high energy X-ray diffraction in-situ tensile testing at elevated temperatures, alongside the non-oxide strengthened base steel as a point of comparison. The single crystal elastic constants of both steels are experimentally determined through analysis of the diffraction peaks corresponding to specific grain families in the polycrystalline samples investigated. The effect of temperature on the evolving dislocation density and character in both materials is interrogated, providing insight into deformation mechanisms. Finally, a constitutive flow stress model is used to evaluate the factors affecting yield strength, allowing the strengthening contribution of the oxide particles to be assessed, and correlation between the thermally driven microstructural behaviour and macroscopic mechanical response to be determined.

中文翻译：

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用于先进聚变反应堆的氧化物弥散强化 EUROFER97 钢的弹性和拉伸性能的原位同步加速器研究

通过引入抗蠕变纳米氧化物颗粒来增强低活化铁素体马氏体钢的机械性能，产生了一类氧化物弥散强化钢，这种钢作为未来核聚变反应堆中第一壁支撑结构材料的候选材料引起了人们的极大兴趣。在目前的工作中，使用高温下同步加速器高能 X 射线衍射原位拉伸试验以及非拉伸试验研究了温度对 0.3 wt% YO 氧化物弥散强化钢 EUROFER97 的弹性性能和微观力学的影响。氧化物强化基础钢作为比较点。两种钢的单晶弹性常数是通过分析与所研究的多晶样品中特定晶粒族相对应的衍射峰来实验确定的。研究了温度对两种材料中不断变化的位错密度和特性的影响，从而深入了解变形机制。最后，使用本构流动应力模型来评估影响屈服强度的因素，从而可以评估氧化物颗粒的强化贡献，并确定热驱动微观结构行为和宏观机械响应之间的相关性。