ISO 20728:2018

Corrosion of metal and alloys — Determination of resistance of magnesium alloys to stress corrosion cracking

Scope

This document specifies a method for the determination of resistance to stress corrosion cracking (SCC) of magnesium alloys intended for use in structural applications (such as magnesium front end, gearbox and clutch housing units, steering column parts, shift actuators, valve covers and housings, brackets and intake manifold blades, electronic devices, power tools and medical equipment). The method allows determination of the resistance to SCC as a function of the chemical composition, the method of manufacture and heat treatment of magnesium alloys.
The document is applicable to cast and wrought magnesium alloys in the form of castings, semi-finished products, parts and weldments and covers the method of sampling, the types of specimens, the loading procedure, the type of environment and the interpretation of results.
The document allows assessment of the relative performance of materials and products in environments containing chlorides or sulphates, provided that the failure mechanism is not changed, but does not qualify a material or product for service application.