Development of micro-Laue technique at Shanghai Synchrotron Radiation Facility for materials sciences

Abstract

Synchrotron radiation-based micro-Laue technique has showcased great application potentials in materials science study for its unprecedented crystal orientation and lattice strain/stress resolution. Here we report the updated progress in the development of the micro-Laue technique on the X-ray test beamline at Shanghai Synchrotron Radiation Facility. So far, 40 µm (h) × 50 µm (v) X-ray beam spot is routinely obtained, with the convergent angle of 0.2 mrad (h) × 0.12 mrad (v). Area scans are conducted on a GH3535 Ni-based superalloy base metal and weld joint with the same chemical composition. By analyzing the tremendous amount of Laue diffraction patterns using in-house developed software packages, the crystal orientation, elastic strain, and defect distributions are mapped and investigated. Such a successful proof-of-principle study offers first-hand experience on the further optimization of the design and construction of the scanning micro-Laue facility on the superbend beamline with improved spatial resolution and multiple functions for simultaneous chemical fluorescence mapping and in-situ microstructural evolution studies. The micro-Laue diffraction beamline at Shanghai Synchrotron Radiation Facility will provide a versatile and powerful tool for the orientation and strain/stress mapping combined with phase identification with micron-sized spatial resolution.