Pre-treatment of metals prior to painting

Other related articles discuss Pre-treatment of metals prior to painting, Paint primers... 

Further detail may be found in articles on Pre-treatment of metals prior to painting, Pre-treatment of copper, Thermal spray processes and Rubber to metal bonding - pre-treatments. 

The importance of a clean surface for painting is paramount (see Engineering surfaces of metals). For metallic substrates, either mechanical or chemical surface treatment is almost always needed to remove surface contamination and promote adhesion. Chemical pre-treatment of metals prior to painting is an effective method of surface conversion that can provide both corrosion resistance and improved paint adhesion. For ferrous metals, the most common chemical pre-treatment is a phosphate for aluminium (and many other non-ferrous metals), the most effective pre-treatment is chromate. Metals must first be cleaned with an alkaline cleaner and then rinsed before they can be converted chemically in an immersion bath or by spray. 

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