Quantification of Inhomogeneous Ceramics using SEM XRF with FlexiSpot

Ceramic materials play a vital role in human activities due to their versatile properties and wide-ranging applications, which are essential for modern living, industry, and innovation. Typically, ceramics are heterogeneous rather than homogeneous, meaning their structure and composition vary throughout. Understanding the average composition of ceramics over a large area is crucial for determining whether they meet performance standards, safety guidelines, and regulatory requirements. Furthermore, compositional analysis offers a scientific foundation for improving and optimizing ceramic materials across diverse applications.

Micro-XRF on SEM, also known as SEM XRF, using our unique XTrace 2 X-ray source with FlexiSpot function facilitates the measurement of inhomogeneous and irregular shaped samples over a range of spot sizes from 10 µm to 500 µm. Via the automatic retraction of the X-ray source with just a click, the spot size can be increased to several hundreds of µm. Using a larger spot area improves the reproducibility of the analyses, offering a better representation of the sample's average composition.

As illustrated in Figure 1, five positions on a ceramic specimen were selected for analysis. The measurements were carried out with two different spot sizes (30 µm and 180 µm respectively) at a constant acquisition time of two minutes.

Fig. 1 SEM images of a ceramic sample showing the measurement points with two different spot sizes: a) spot size 30 µm and b) spot size 180 µm.

Table 1: The quantification results indicate that the ceramic mainly consists of SiO2, CaO, Al2O3, and Fe2O3, with trace amounts of K2O, MgO, TiO2, Mn, Zn, Sr and Zr. Data precision improves with a 180 µm spot size compared to 30 µm, as larger spot sizes capture a more consistent average composition across a wider area, while smaller sizes reflect localized compositional variability.

Table 1 shows the quantification results acquired with small (30 µm) and large (180 µm) spot size. The results demonstrate that the ceramic is predominantly composed of SiO₂, CaO, Al₂O₃ and Fe₂O₃, with trace quantities of K₂O, MgO, TiO₂ and Mn, Zn, Sr and Zr.

When looking at the relative standard deviation, it is easy to see that scattering in the data recorded with a spot size of 180 µm is significantly lower (higher precision) than the data recorded with a spot size of 30 µm. This phenomenon can be attributed to the fact that a smaller spot size provides sample information from a small area that can vary greatly in composition from region to region. Conversely, increasing the spot size provides information from a larger area that approximates the average composition of the sample and thus remains relatively consistent across the different measurements.

In summary, Micro-XRF on SEM enables the efficient and reproduceable quantification of inhomogeneous and irregularly shaped samples. XTrace 2’s unique FlexiSpot function provides varying adaptive spot sizes, up to several hundred micrometers, with an automatic retraction of the X-ray source in a click.

The convenient automatic retraction of the X-ray source improves data reproducibility by adjusting to a larger spot area to provide a more precise representation of the sample's average composition.

Discover QUANTAX Micro-XRF Contact an expert