ISO 9455-13:2017

Overview

ISO 9455-13:2017 - "Soft soldering fluxes - Test methods - Part 13: Determination of flux spattering" specifies a qualitative laboratory method to estimate the tendency of liquid soft soldering fluxes to spatter during use. The standard applies only to liquid fluxes (see ISO 9454‑1) and is not applicable to flux‑cored solder wire or solder pastes. The method yields a comparative result: either absence of projections or formation of projections, or a comparison versus a reference flux.

Key topics and requirements

• Scope: Qualitative (comparative) test for liquid flux spattering tendency; excludes flux‑cored wire and solder pastes.
• Principle: A measured droplet of flux is placed on a cleaned steel test plate which is heated by contact with a molten solder bath; the plate is examined for spattering.
• Test specimen: Liquid flux as defined in ISO 9454‑1.
• Equipment:
  • Rectangular solder alloy bath (~150 mm × 100 mm) containing ≥4 kg of tin‑based solder (ISO 9453), surface within 5 mm of the bath rim; bath maintained at (400 ± 10) °C.
  • Steel test plates, 1 mm thick, cut from deep‑drawing quality carbon steel (ISO 3574), sized to exceed the bath rim by 10 mm in each direction.
  • Silicon carbide (SiC) abrasive cloth, grade 180, for cleaning the plate surface.
  • Finely graduated pipette for delivering (0.1 ± 0.01) ml of flux.
• Procedure:
  • Clean plate with SiC cloth immediately before test.
  • Deposit 0.1 ml flux at plate center; place plate on bath rim so flux faces down; keep bath air calm.
  • After 3 minutes, remove and visually inspect for spatter.
  • Repeat on three plates; report the average qualitative result.
• Results reporting:
  • Record as “absence of projections” or “formation of projections”.
  • Optionally compare test flux to a reference flux and report as “equal”, “superior” or “inferior” relative to the reference.
  • Test report must identify sample, method reference, results, any anomalies and test date.

Applications and users

This standard is useful for:

• Flux manufacturers conducting product development and quality control.
• Electronics and soldering process engineers assessing flux behavior in wave or manual soldering operations.
• Test laboratories performing comparative flux evaluations for procurement or specification compliance.
• Supplier qualification and failure‑analysis teams investigating spatter‑related defects (solder bridges, contamination, safety risks).

Keywords: ISO 9455-13:2017, flux spattering, flux spatter test, soft soldering fluxes, liquid flux test, soldering flux quality.

Related standards

• ISO 9454‑1 - Flux classification and requirements (liquid flux definition)
• ISO 9453 - Tin‑based soft solder alloys (composition)
• ISO 3574 - Cold‑rolled carbon steel plates (deep‑drawing quality)

For official interpretation or to obtain the full method (figures and complete test report format), consult the ISO publication ISO 9455-13:2017.