EN ISO 3923-1:2018 PDF

Overview

EN ISO 3923-1:2018 - "Metallic powders - Determination of apparent density - Part 1: Funnel method" - specifies a standardized funnel procedure to determine the apparent density (bulk density in a loose condition) of metallic powders used in powder metallurgy. The method is intended for powders that flow freely through a 2.5 mm orifice and can be adapted for powders that need a 5.0 mm orifice. It defines required apparatus, sampling, test procedure, result calculation and reporting under controlled conditions.

Key topics and technical requirements

• Scope: Apparent density measurement by the funnel method for metallic powders; powders that do not flow through a 5 mm orifice are covered by ISO 3923‑2.
• Accepted funnels:
  • Hall funnel: 2.5 mm orifice, 60° cone (ISO 4490).
  • Gustavsson funnel: 2.5 mm orifice, 30° cone (ISO 13517).
  • Carney funnel: 5.0 mm orifice, 60° cone (Annex A; ASTM B417 dimensions).
• Cup and stand:
  • Cylindrical cup volume: 25 cm³ ± 0.03 cm³; internal diameter preferably 28 mm ± 0.5 mm (30 mm ±1 mm acceptable).
  • Funnel orifice mounted 25 mm ± 0.5 mm above cup on a vibration‑free stand, coaxial alignment required.
• Apparatus material: Non‑magnetic, corrosion‑resistant metal with polished inner surfaces to avoid distortion and adhesion.
• Balance accuracy: ±0.01 g.
• Sample: Minimum sample volume 100 cm³ to permit three test portions.
• Procedure highlights:
  • Fill cup by pouring powder through funnel until overflowing, level with a non‑magnetic straight‑edge without compression.
  • If necessary, use 5 mm funnel or initiate flow with a single poke using a 1 mm wire (wire must not enter the cup).
  • Tap cup lightly to settle powder for transport and weigh the powder mass.
  • Perform three determinations.
• Result expression: Apparent density = mass / 25 cm³; report mean to nearest 0.01 g/cm³ and include range if scatter >1% of mean.
• Precision:
  • Repeatability suspect if duplicate tests differ by >0.03 g/cm³ (95% confidence).
  • Reproducibility suspect if different labs differ by >0.05 g/cm³ (95% confidence).
• Drying: Powder generally tested as‑received; drying permitted in vacuum or inert gas if oxidation is a concern; do not dry if volatiles present.

Applications and users

• Practical for quality control, incoming inspection and process monitoring in powder metallurgy, metal additive manufacturing, MIM (metal injection molding) and component sintering processes.
• Used by laboratories, manufacturers, material engineers, and procurement teams to assess powder flowability, packing behavior and to specify materials for forming, filling and sintering operations.

Related standards

• ISO 3923-2 - Scott volumeter method for powders that do not flow through a 5 mm orifice.
• ISO 4490 - Hall flowmeter (calibrated funnel) method.
• ISO 13517 - Gustavsson flowmeter method.
• ASTM B417 - Carney funnel dimensions (referenced for Annex A).