Why ?
- Because it is important to bear in mind that the Aluminum surface is soft. There will be scratches if two parts touch each other, or a screwdriver or scissor touches when opening the wrapping. This is mechanical damaging and it happens due to the fact that aluminum is a soft material.
- Because the aluminum surface is only corrosion resistant in the area of pH 4.5 - 8 and your sweat could be more acidic than that and also containing chloride. If the parts are stored in a humid area, if you are using cardboard which contains acid, or other metallic particles are found in the area where the unprotected aluminum surface is found. This is chemical damaging and due to the fact that aluminum is a reactive material.
This photo shows how a surface is often found by the anodizer. Some of this will be removed during the process steps but the more severe cases will show after the anodizing, as seen in the below photo.
Photo taken with courtesy from Mr. Barry Ellards presentation at the Aluminum Anodizers Council 16th Annual International Anodizing Conference & Expo, Lincolnshire, 2007
If you find this article useful and you would like to know more please contact me blog@aluconsult.com
__________________________________________________
