) is calculated by dividing the total number of "hits" by the total number of points applied across all fields. 3. Statistical Confidence and Precision
: A transparent reticle placed in the eyepiece, or a digital grid superimposed onto a monitor via imaging software. astm e562-19e1
The ASTM E562-19e1 standard is built on a fundamental principle of stereology: the relationship between two-dimensional measurements made on a plane (like a polished cross-section of a material) and the three-dimensional structure of the material itself. According to the standard, "a grid with a number of regularly arrayed points, when systematically placed over an image of a two-dimensional section through the microstructure, can provide, after a representative number of placements on different fields, an unbiased statistical estimation of the volume fraction of an identifiable constituent or phase". ) is calculated by dividing the total number