Without effective surface preparation prior to phosphating, coating weights, corrosion resistance and part appearance can all be negatively affected. When selecting pretreatment chemistries, consider the following:
- Type of phosphate being applied – iron, manganese, zinc, zirconium
- Application – spray, immersion or both
- Substrates – ferrous or non-ferrous or both
- Surface condition & soils – machining oils, grease, rust, carbon scale, etc.
- Cleaner technology – oil splitting, emulsifying – acidic, alkaline or neutral
High volume high production phosphate lines require cleaners that can handle heavy soil loading. New advancements in surfactants and other cleaning agents help improve oil removal and retention in solution so it does not redeposit back on the parts. JSA laboratory services provide the tools to test and manage cleaners that maximize the production capabilities of your process line.
Laboratory testing procedures to determine the best product for the application:
- Parts cleaning study – test production parts when possible
- Oil removal study – panels are coated with the raw machining fluids/oil & immersed in multiple cleaners
- Oil split test – used to determine when a production cleaner should be dumped
- Dyne ink test – surface finish test to determine effectiveness of a cleaner