ISO 13517:2020

Overview

ISO 13517:2020 specifies a standardized method to determine the flow rate of metallic powders using a calibrated funnel (Gustavsson flowmeter). The test measures the time required for 50 g of a free‑flowing metallic powder to pass through a specified orifice and reports results in seconds per 50 g (s/50 g). The procedure supports routine quality control and comparative evaluation in powder metallurgy, including powders for hardmetals and mixes containing organic additives.

Key Topics

• Principle: Measure elapsed time for 50 g of powder to flow through a calibrated funnel orifice (Gustavsson flowmeter).
• Apparatus: Calibrated funnel of defined dimensions, non-magnetic corrosion-resistant material; rigid stand with vibration‑free base; balance accurate to ±0.05 g; timing device accurate to ±0.1 s; reference grit for calibration.
• Calibration: Manufacturer calibration yields an average reference flow (stamped on the funnel). Typical calibration target is 40.0 s ± 0.5 s for the reference grit. Users shall verify calibration periodically and apply a correction factor when the reference flow deviates from the stamped value.
• Sampling and test portion: Minimum sample mass 200 g. Test portion normally 50.0 g ± 0.1 g; alternative automated option 90–110 g with recalculation to s/50 g. Perform three determinations per sample.
• Procedure highlights: Transfer test portion to the funnel with the orifice closed; open orifice and start timing; stop timing when last powder leaves orifice. A single slight tap to start flow is permitted; if flow does not occur the powder is considered not flowable by this method.
• Results and reporting: Report the arithmetic mean of three determinations in s/50 g (rounded to the nearest second). Apply any calibration correction factor when required.

Applications

• Routine quality control of metallic powders in powder metallurgy and hardmetal production.
• Comparative assessment of powder flowability for process selection (e.g., pressing, filling, additive manufacturing feedstocks).
• Supplier and purchaser acceptance testing where a reproducible, simple flow-rate metric is required.

Related Standards

• ISO 2768-1 - referenced for dimensional tolerances of new funnels.
• ISO 5725-2 - used to determine repeatability and reproducibility (precision statement) for this method.

Practical value

This method provides a simple, reproducible numeric indicator (s/50 g) of powder flow behavior using the Gustavsson flowmeter. Proper calibration, careful sampling, and adherence to the specified procedure produce consistent data useful for quality control, process troubleshooting, and supplier specification. The standard also defines reporting requirements so results are comparable between laboratories.