ISO/TC 44/SC 13 - Brazing materials and processes

This document specifies three test methods for investigating brazeability. A spreading test shows testing method with measurement of the spread area of the filler metals. A T-joint test describes a scheme to construct a T-shape design by the test pieces and a testing method. A varying gap test describes a test piece and a testing method for assessing the influence of the various parameters which can influence brazing during manufacture as a function of clearances.

This document specifies the classification of fluxes used for brazing metals and characterizes these fluxes on the basis of their properties and use, and gives technical delivery conditions and health and safety precautions. This document covers two classes of flux, FH and FL. Class FH is used for the brazing of heavy metals (steels, stainless steels, copper and its alloys, nickel and its alloys, precious metals, molybdenum and tungsten). Class FL is used for the brazing of aluminium and its alloys.

ISO 3677:2016 specifies designations for filler materials for soldering and brazing, on the basis of their chemical composition. For brazing materials only, the designation includes their solidus/liquidus temperatures. This International Standard deals with the metallic part of filler materials used in soldering and brazing products, e.g. foils, wires, rods, pastes, flux coated rods/wires, flux cored rods/wires, etc.

ISO 17672:2016 specifies the compositional ranges of a series of filler metals used for brazing. The filler metals are divided into seven classes, related to their composition, but not necessarily to the major element present.

ISO 18279:2003 details a classification of imperfections that can occur in brazing joints. In addition guidance is provided on quality levels and suggested limits for imperfections are detailed. For requirements not covered by this standard, reference is to be made to other sources, e.g. statutory regulations, codes of practice and technical delivery conditions. No information is given on how imperfections are to be assessed in individual cases because this depends on the requirements for the particular brazed joint. These imperfections are not always detectable by the use of non-destructive testing alone. The standard covers only imperfections that can occur in connection with brazing without the effect of any additional service loads. Only the type, shape and position of such imperfections are covered; no indication is given of the conditions of occurrence or causes. For requirements for brazed joints which are relevant and essential to the particular function of the component, reference should be made to the relevant documentation, e.g. manufacturing documents or procedure sheets. This International Standard does not lay down requirements for acceptance levels for imperfections since these will differ very markedly, depending on the application, but it does suggest some quality levels which may be of value in the absence of more detailed information.

Defines the principles and the technique of the tests designed to determine the conventional mechanical characteristics of assemblies produced with soft solders and brazing filler metals. Specifies also a method of interpreting the results obtained. Applies to joining materials and their fluxes which are used for soldering and brazing of ferrous and non-ferrous metals and alloys.

Describes the procedures designed to produce an analysis sample representative for each batch of soft solder in the consignment in the folowing details: unit of product, selection of the batch sample, preparation of the test sample sticks from the batch sample, preparation of the analysis sample, testing of individual units of product, preservation of the analysis sample.

Specifies a testing method for assessing the influence of the various parameters which can influence brazing during manufacture as a function of clearances. The test piece described gives guidance about the effects of brazing variables on filler metal flow when capillary gaps of different dimensions are used.