A size cut and a distribution are not the same thing
An expression such as 15–53 µm defines the product’s nominal particle size cut. D10, D50 and D90 are cumulative percentiles based on the distribution basis used. The measurement report must state whether the basis is volume or number, and the method.
D50 alone is not enough
Two powders with the same D50 can have different fine and coarse tails. Therefore evaluate the D10–D90 range, the distribution curve and the fraction outside the requested cut together. The CNPC catalogue tables give D10, D50 and D90 values alongside the size cut.
Matching to the machine
Finer powder does not automatically mean better printing. Spreading, flow, powder feeding and layer thickness must be evaluated together. Compare the cut recommended by the powder manufacturer with the machine supplier’s material specification.
Ask for comparable reports
Request the measurement instrument, sample preparation method and reporting units within the same framework. Do not tie the acceptance criterion to a single average value.
Source: CNPC POWDER Company Catalog, printed pp. 3–4, 14–23; powder properties and product comparisons. Catalogue data is a reference for material selection; the datasheet, certificate of analysis of the delivered batch and application tests prevail.