The Development of Aluminium Alloy AA7032 for High Pressure Gas Cylinders

The purpose of this paper is to discuss issues raised during the development of a 7XXX series aluminium alloy (AA7032) suitable for use in the manufacture of high pressure compressed natural gas (CNG) cylinders for automotive applications, and specifically the effect of impurity levels on cylinder properties. Material was produced with a range of iron and silicon levels, and a comprehensive microstructural characterisation and mechanical property assessment was completed. Failure mechanisms in association with impurity levels were identified and their significance with respect to cylinder integrity determined.