ISO 3677:2024 PDF

Overview

ISO 3677:2024 - "Filler metal for brazing - Designation" defines a standardized naming system for the metallic part of brazing filler materials based on chemical composition and melting range. It applies to metallic filler components used in foils, wires, rods, pastes, flux‑coated rods/wires and flux‑cored rods/wires. The designation explicitly includes solidus and liquidus temperatures to support process control and material selection.

Key topics and requirements

• Designation structure: three parts separated by dashes:
  • First part: the letter B (for brazing).
  • Second part: group of chemical symbols and nominal mass percentages indicating alloy constituents.
  • Third part: solidus/liquidus temperatures in °C, separated by a slash.
• Composition rules:
  • Major element chemical symbol first, followed by its nominal mass percentage (whole number, ±1 accuracy).
  • When an element has a specified range, use the mean rounded to the nearest whole number (round-even on ties); if only a minimum is given, use the rounded minimum.
  • Other elements listed in decreasing nominal percentage; ties resolved by decreasing atomic number.
  • Elements with nominal values