微聚焦三维X射线小角散射（3D-SAXS）技术是一种可以无损重建多相非均匀物质内部三维纳米结构信息的新型实验方法。该方法在表征三维介观尺度结构方面具备实时无损等特点，拥有广泛的实验用途。实现这一方法的必要关键条件是需要有高分辨高亮度的X射线光源作为基础。目前国际上3D-SAXS方法学正处于发展阶段，也是当前相关先进同步辐射光源积极发展的新方法；国内有关3D-SAXS方面的研究则尚处于空白阶段。本研究基于国内第三代同步辐射装置（上海光源）小角散射相关线站拟建立三维空间高分辨3D-SAXS实验方法学，针对矢量信息重建发展一套相应的高效层析重建算法，以实现在线分析重构样品介观尺度结构并将其应用于聚乳酸注塑成型过程的结构表征。期望对注塑成型过程中材料内部结构形成“精细化”控制，打通“加工-结构-性能”的内在联系，初步实现所谓的“定构加工”。

Micro focused three-dimensional X-ray small angle scattering (3D-SAXS) is a new experimental methodology for nondestructive reconstruction of internal 3D nanoscopic structure in multiphase and non-uniform object. This method has an in-situ and nondestructive performance with a wide potential applications in the characterization of 3D mesoscopic structures. A key to achieve this method is the condition of high-resolution high-luminance x-ray source. Currently, 3D-SAXS is a positive developing method in the international advanced synchrotron radiation facilities and preliminarily has been applied to the study of structural properties and functions in soft material. By contrast, research about 3D-SAXS in domestic is still in the blank. Based on the small angle x-ray scattering beamlines (BL19U2, BL16B1) in domestic third-generation synchrotron radiation facility (Shanghai synchrotron radiation facility), this project plans to establish the high-resolution 3D-SAXS experimental methodology and develop an efficient computer tomography reconstruction algorithm for vector information reconstruction to achieve the reconstruction of mesoscopic structures in multiphase samples. Furthermore, It will be applied to characterize the structure changes in the polylactic acid injection molding process. It will give a chance to form a "fine" control of internal structure of materials during the injection molding process and establish the relationship between the final performance and the processing parameters as well as the product structure. This will help us to open up the "process - structure - performance" internal relations and to achieve the initial realization of the so-called "fixed configuration process " in polylactic acid injection molding applications.