In the X-ray Fluorescence analysis (XRF) field, it may fairly be said that sample preparation can be the largest factor that cause analysis error. Especially for the analysis of powder samples, as mentioned in the previous edition [Sample preparation for X-ray Fluorescence Analysis I.], heterogeneity effects such as grain size effect, mineralogical effect and segregation can result in analysis error because of its effect on the X-ray fluorescence intensity. When more precise analysis is required, it is recommended to analyze the sample after pulverization to eliminate the grain size effect and segregation as much as possible. For the fusion bead method which can remove the influences of grain size and mineralogical effects, the pulverization of the sample beforehand may be a key point in successfully preparing a homogeneous fusion bead sample with high reproducibility.
This issue describes the important points for pulverization to make powder samples with particle size less than 50 μm.