Standard Test Methods for Estimating Average Particle Size of Metal Powders and Related Compounds Using Air Permeability
This test method provides a procedure for determining the envelope-specific surface area of powders, from which is calculated an “average” particle diameter, assuming the particles are monosize, smooth surface, nonporous, spherical particles. For this reason, values obtained by this test method will be defined as a Fisher Number. The degree of correlation between the results of this test method and the quality of powders in use will vary with each particular application and has not been fully determined.
