NADCAP certified passivation refers to a process that is used to treat metal surfaces so as to reduce the impact of environmental factors such as air and water. When you think about plating, which is a common practice that is used to coat a surface with a metal oxide so as to slow down the process of oxidation thereby providing it with a greater ability to resist corrosion. Passivates can be found available in different colors that include clear blue-black, yellow and green. All this can also enhance the aesthetic appearance of a material or make it easier for a part to be identified.
NADCAP certified passivation is normally used in zinc or zinc alloy plating especially when it is used as a post-treatment process in order to prevent the appearance of white rust; this is a rapidly spreading localized form of rust that is most prevalent with zinc. The most common materials that are used during the NADCAP certified passivation process for zinc, magnesium and aluminum include Chrome, Cobalt, Manganese, Molybdenum, Nickel, Tungsten, and Vanadium. Consumers can now access chrome-free Passivates; this is an alternative process of passivation that provides corrosion protection in addition to improved coloring ability especially when you are thinking about a black spectrum. One additional advantage that is associated with chrome-free NADCAP certified passivation is a finishing lacquer that may be applied after the process so as to create a tougher protective seal.
Even though steel is known to be naturally resistant to corrosion, it still remains susceptible to rusting or rather roughing in a few environmental conditions. NADCAP certified passivation may become necessary but this will be determined by the grade of stainless steel plating so that it can maintain the desired finish and function. The most common methods of passivation of stainless steel use a nitric acid based or citric acid passivation bath at different levels of temperature and concentration. Once the material has undergone the surface cleaning process, the specific method and type of NADCAP certified passivation will depend on the future application of the part involved. The passivation of stainless steel will remove exogenous iron and create a protective coat that will shield the object from oxidation and rust, clean it from dirt and any other corrosive compounds and elements.
Always insist on NADCAP certified passivation at the level of chrome-free passivation because of its inherent corrosion protection. The best passivation should be able to comply with the most stringent regulations with great emphasis on the current standards as required for the passivation of stainless steel and any other metallic compounds and elements. Anything less than the highest quality NADCAP certified passivation for zinc plating and stainless steel passivation will almost always lead to disappointment.