Weldability aspects in the design and fabrication of aluminium structures subjected to fatigue loads. Part 1. Effect of welding on the structural integrity of joint types designed for repairing aluminium ship sections

Aluminium alloys are increasingly being used as welded construction materials in order to achieve more lightweight structures. This has partly been made possible by the advances in power source technology, which has created new productive welding techniques for use also with aluminium. However, the specific properties of the various aluminium alloys are relatively little known, and the experience gained from steel welding cannot, as such, be applied to aluminium. This complicates successful design and fabrication of welded structures and has an adverse effect on the productivity and quality of welding as well as the structural strength of the welded joints. The Laboratory of Production Engineering and the Metals Laboratory of the Technical Research Centre of Finland (VTT) have participated in a Nordic research project entitled "New methods for joining of aluminium". The results from Finnish work of this project will be presented in a report to be published in two parts. This Part l of the report will evaluate the effects of welding on the structural integrity of some joint types primarily designed for repairing ship sections and sea crafts made from 6xxx (AlSiMg) series alloys.