Shape Correction for Metal Samples
Since metal reference materials have recently become available, there has been an increase in demand for accurate measuring by calibration curves created using metals standards. Nonetheless, consideration of sample shape and size is required for measuring metals using the calibration method. Fluorescent X-rays decrease as sample size decreases and the concentration calculated by the calibration method is undervalued. Hitachi High-Tech Science resolved this problem by developing a correction function using scattered X-rays. The left-hand figure below shows the spectrum of Pb in a brass sample. The right-hand figure shows scattering from the same sample. Both figures exhibit a significant difference between the height of peaks resulting from enough irradiation ("Whole" with Blue color) and peaks without enough irradiation ("Right Half" with Pink color and "Back Half" with Red color). This phenomenon can be verified for both Pb and scatter. Metal samples can be more accurately measured by the correction function that uses these differences.
The effects from shape can be reduced by taking the ratio of both when there is correlation between scattered X rays intensity and fluorescent X-ray intensity.