In order to better understand the international standard ASTM B 213 about determining hall flow rate of metallic powders using a hall flow meter/hall flowmeter, user has to understand the important terminology before that:

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-Definitions of powder metallurgy terms,user has to refer to ASTM B 243.

-Flow Rate
The definition of a flow rate is that the time needed for a powder sample of standard mass (50g) to flow through an orifice in a standard instrument (Hall Flow Meter Funnel) according to a specified test procedure.