IEC 62739-3:2017

Overview

IEC 62739-3:2017 - "Test method for erosion of wave soldering equipment using molten lead‑free solder alloy - Part 3: Selection guidance of erosion test methods" - defines a structured selection methodology for choosing appropriate laboratory test methods to evaluate erosion of metal materials (with or without surface processing) used in lead‑free wave soldering equipment (solder baths and components in contact with molten solder).

This part of the IEC 62739 series helps users map real-world stresses in wave soldering to accelerated erosion tests and choose the right test conditions and measurement methods.

Key topics and technical requirements

• Selection methodology: Guidance to correlate field stresses (temperature, flow, contact dynamics, dross) with laboratory test methods.
• Test method overview: References to specific accelerated tests - e.g., rotation tests commonly specified at 350 °C (for unprocessed metals) and 450 °C (for surface‑processed materials), including options with 2 mm bending to simulate mechanical stresses.
• Common test items:
  • Specimen preparation and surface processing considerations.
  • Solder alloy selection consistent with IEC 61190‑1‑3 (electronic grade lead‑free solders).
  • Accelerated stress parameters: test temperature, rotation speed, immersion time and bending stress.
  • Dross management: generation intervals, removal methods and remaining molten solder volume after dross removal.
  • Erosion depth measurement: post‑test treatment, local (focal) vs general (uniform) erosion depth assessment and evaluation regions.
• Supportive annexes: guidance on selecting test temperature, duration and bending stress; measurement techniques and accuracy; erosion mechanisms; and thermal acceleration behavior.

Practical applications and users

This standard is essential for:

• Manufacturers of wave solder baths, solder pot components and replacement parts (material selection and lifetime prediction).
• Materials suppliers and surface‑treatment providers (stainless steels, nitriding, coatings) validating corrosion/erosion resistance to lead‑free molten solder.
• Reliability and process engineers in electronics assembly seeking to specify or evaluate component longevity under wave‑solder conditions.
• Independent test laboratories performing accelerated erosion testing and quality assurance.
• Procurement and conformity teams requiring standardized test selection for supplier qualification.

Related standards

• IEC 62739‑1:2013 - erosion test method for metals without surface processing
• IEC 62739‑2 - erosion test method for metals with surface processing
• IEC 61190‑1‑3 - requirements for electronic grade lead‑free solder alloys
• IEC 60068‑2‑20 - solderability and resistance to soldering heat tests

Keywords: IEC 62739-3, erosion test, wave soldering, lead-free solder, solder bath, rotation test, dross management, erosion depth measurement, surface processing.