What is the Difference Between XRD and XRF?
X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD) are two separate but complementary analytical techniques that use an X-ray source and detector. Both measure the sample’s response to the X-rays, but their measurements provide different, yet supplemental, information about the sample. XRF provides the elemental data and XRD provides mineralogical/crystallographic data. The accuracy of phase identification and quantification in a sample can be improved by using both techniques.
X-Ray Fluorescence (XRF) is a non-destructive analytical technique used to determine the elemental composition of materials. It identifies and quantifies elements by percentage or parts per million (ppm). XRF analyzers determine the chemistry of a sample by measuring the characteristic fluorescent (or secondary) X-rays emitted that are unique to each specific element. However, while this technique determines the elemental composition of the sample, it does not provide information about the element’s phases or polymorphs. Results for this technique are provided as a graphical output.
Applications for XRF analysis include use in cement manufacturing, mining, paints, chemicals, polymers, petroleum, metallurgy, and environmental and forensic investigations. Portable XRF analyzers are available and can be used in the field.
X-Ray Diffraction (XRD) is a nondestructive analytical technique that provides quantitative mineral phase analysis, including crystallography and the relative fraction of multiphases of materials. It can distinguish the major, minor and trace minerals present. The diffraction pattern produced when a crystalline material is analyzed reveals the material’s crystalline/lattice structure. Qualitative results can be obtained when the resulting diffraction pattern of an unknown sample is compared with a library of known patterns.
Applications for XRD analysis include crystallography, surface and thin film analysis, identification of phases in an unknown sample, and phase quantification of a known sample.
XRF and XRD
These two complementary techniques provide both qualitative and quantitative material characterization. They are used together in a variety of applications for elemental analysis, such as in mining and geology, in cement manufacturing, for sample identification, quality control, regulatory compliance, and environmental analyses.