ABSTRACT
One of the advantages of aluminium is that it is a naturally durable metal which can be used in many applications without the need for added protection against the ravages of atmospheric or other chemical attack. Profiled building sheet, greenhouse frames, ladders, and lorry bodies are examples of uses where the natural ‘mill’ finish of aluminium is perfectly acceptable. Immediately aluminium and aluminium alloys are exposed to oxygen a very thin layer of aluminium oxide forms on the metal’s surface. The diameter of the pores and the thickness of the barrier layer that is continuously formed during the anodizing process between the underlying metal and the growing cells are controlled not only by the particular electrolyte used but also by the temperature and voltage applied. Medical and scientific instruments, electronic components and cabinets, shower cubicles and lighting units are just a few examples of diverse applications of anodized aluminium.
