ADVANCED MATERIALS & PROCESSES | JANUARY 2026 15 One of the advantages of materials characterization is the variety of techniques available to solve problems, and an under- utilized secret weapon in materials characterization is combining various techniques. One characterization method may provide illuminating answers, but in tandem, multiple methods can be truly enlightening. Electron backscatter diffraction (EBSD) and x-ray diffraction (XRD) are two methods that are extremely useful when used together. Electron backscatter diffraction data is collected within a scanning electron microscope (SEM), exploiting the interaction of source electrons with sample electrons, providing information about the crystal structure of the sample. The typical area investigated can range from the micron to the millimeter scale and the results describe grain size, shape, and orientation of the material[1]. X-ray diffraction is collected with a diffractometer and produces a spectrum of intensity of x-ray signal over an angular range, based on Braggs Law. The data is often collected from approximately a centimeter-sized area and provides information about the phases present in the material[2]. Both methods can be used to understand textures within the material attributed to the dominating orientation of crystals in the material, presented with pole figures. The crystallographic information from both methods can also be used to identify phases within the material in question. While valuable on their own, EBSD and XRD can be invaluable in tangent. This article presents two case studies, both conducted at NASA Glenn Research Center, that demonstrate the power of combining EBSD and XRD[3,4]. CASE STUDY 1: TEXTURE AND PHASE IDENTIFICATION WITH XRD AND EBSD Introduction. Oxide dispersion strengthening (ODS) has been shown to be an effective method for improving high-temperature creep resistance in materials like superalloys. Additive manufacturing (AM) has provided a successful method to produce oxide dispersion strengthened metal superalloys. These AM ODS superalloys have superior mechanical strength at high temperatures when compared to nonODS materials[5-7]. However, metal AM processes like laser-powder bed fusion can induce significant texture in the build material due to high thermal gradients along the build direction[8]. The grain textures of these AM materials can have a significant impact on their mechanical strength, and therefore understanding texture in the material is critical[8-10]. As part of a study evaluating the creep and tensile rupture failure modes in AM, ODS and non-ODS, Ni-based superalloy samples, the grain microstructure and textures were evaluated using EBSD and XRD. Methods. Samples of a NiCrAl model superalloy were produced by laser powder bed fusion both with and without additions of Y2O3 oxide powder. These ODS and non-ODS samples underwent hot isostatic pressing and solution heat treatments prior to being sectioned and metallographically prepared. XRD texture measurements were performed on a PANalytical Empyrean Series 2 diffractometer using Cu Kα radiation. The area scanned was approximately 15 mm by 17 mm. Phase identification measurements were also collected using a Bruker D8 Advanced diffractometer using Cu Kα radiation. EBSD was performed on a Tescan MAIA3 field emission SEM at 20 kV accelerating voltage and with an Oxford HKLNordlys System and Aztec software. Approximately a 0.9 mm by 0.7 mm area was scanned. Results and Discussion. The non-ODS materials showed equiaxed grains and random texture. The ODS materials had elongated grains in the build direction and stronger texture in Fig. 1 — (a) Non-ODS grain texture measured transverse to the build direction (indicated by arrow) by EBSD and XRD, plus inverse pole figure from EBSD. (b) ODS grain texture measured with EBSD and XRD, also transverse to the build direction (indicated by arrow), plus inverse pole figure from EBSD. (a) (b)
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