These post treatments which are an integral part of the process are applied in the final rinse stage. The passivation processes are used very dilute at temperatures from ambient to 70°C with process times between one and two minutes.
These treatments have a pronounced affect on the performance of the overall system. On accelerated corrosion tests, these treatments can enhance the performance of lightweight iron and zirconium phosphates by up to one hundred percent and zinc phosphates by around twenty percent.
These post treatments are chrome free replacing the traditional chrome containing products with equivalent performance.
For further technical information on our product range please call Brian on 01204 495818 or email us to see which process meets your individual requirements.
A typical example would be Sealguard NC 426 - Chrome free passivation Process
Sealguard NC 426 is a liquid, chromium free passivation treatment for use in the final stage of pretreatment plants. The process may be used by spray or immersion and eliminates contaminants from phosphated surfaces thus improving the paint adhesion and increasing the corrosion resistance when finished by an organic coating.
Sealguard NC426 considerably increases the corrosion resistance of phosphated ferrous components and is also recommend for use on aluminium and zinc substrates.