Development of new X-ray diffraction system for quantitative analysis of nanoscale defects in alloys

塑性变形金属中的位错引起晶体应变，并由位错阵列形成畴。当用x射线衍射观察这些晶体的应变和畴结构时，随衍射顺序的不同，在x射线衍射线剖面上出现了特殊的形状。在这项研究中，我们开发了一种优化的x射线衍射仪，用于线轮廓分析，并利用最新的线轮廓理论分析了变形金属合金（如铁基和铜基合金）的显微组织。我们成功地分析了位错与孪晶诱导塑性的关系，以及位错对时效析出的影响。

Dislocations in plastic-deformed metals induce crystal strain, and domains developed by the arrays of the dislocations. When these crystal strain and domain structures are observed by X-ray diffraction, peculiar shapes depending on the diffraction order appear in the line profiles of the X-ray diffraction. In this study, we have developed an X-ray diffraction apparatus optimized for the line profile analysis and have analyzed microstructures of deformed metallic alloys such as iron-based and copper-based alloys by using a recent theory on the line profiles. We have successfully analyzed the correlation between dislocations and twinning induced plasticity, and the effects of dislocations on aging precipitation.