The flow time method matters
A result given in s/50 g is the time measured with the specified test set-up. Compare shorter times only under the same method and conditions. A sample that does not flow and a field that was not measured do not mean the same thing.
Two different bulk densities
Apparent density is the mass/volume ratio of the loose powder bulk; tap density is the same ratio after a defined tapping procedure. Neither is the actual density of the printed part. Do not turn the different densities of alloy families directly into a quality ranking.
What does SEM show?
Sphericity, satellite particles, agglomerates and surface appearance can be examined in SEM images. A single selected image may not represent the whole batch; the report must be evaluated together with its sampling method.
Read them together, batch by batch
Particle size distribution, flow, apparent/tap density and chemical analysis together form an acceptance file. Validate the powder choice with this file and with a trial on the machine.
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.