Atmospheric Corrosion of Anodised Aluminium exposed over a Twelve Year Period in the Main Centres of New Zealand

Abstract

A study of the effect of atmospheric corrosion on an architectural grade of aluminium had been made in Christchurch, New Zealand. This initial work was then extended to cover the main centres of the country. A range of test coupons including the as received ‘mill finish’ condition and the identical material protected with three different thicknesses of anodic coatings were exposed at main centre sites plus a rural site for comparison purposes. The initial aim was to produce visual indications of behaviour in the atmosphere and this was later expanded to include weight loss data. After the preparation of the data obtained in a range of Christchurch atmospheres, a twelve year period for the wider range of sites has now elapsed and these results are now reported. The same range of test coupons has also been exposed in an accelerated corrosion rig and the results from this are included for comparison purposes.