Aluminium Materials for Structural Engineering - Essential Properties and Selection of Materials

Many engineers hesitate to use aluminium for structures even though its use would bring real advantages. Very often aluminium is not even taken into consideration as an alternative to steel. Clearly aluminium is a metal and therefore the design and dimensioning processes are similar to those used for steel. There are, however, important physical differences in the materials. Aluminium uses another nomenclature system and there are differences in the procurement procedures of the semi fabricated materials, which may have a certain deterrent effect and work against use of this modern metal. Aluminium has in fact proved itself as a suitable material for load bearing structures for more than one hundred years. However, certain knowledge of aluminium is necessary to design structures. The task of this paper is to cover the most important aspects needed to design in aluminium. It covers the important differences of physical properties compared to steel which need to be understood to design aluminium structures. It covers the influence of heat on the mechanical properties of aluminium. The essential metallurgical aspects are explained to enable understanding of aluminium's nomenclature system for alloys and their temper designations. The effect of these aspects on the available form of semi manufactured aluminium products as sheet, extrusions or forgings, is covered focusing on the wrought materials listed in Eurocode 9.