The Basics of Phosphate Conversion Coatings

The phosphate process is the treatment of a metal surface that produces a reasonably hard, electrically non-conducting surface coating of insoluble phosphate that adheres to the underlying metal. It is used to enhance corrosion resistance, lubricity or as a foundation for subsequent coatings or paint. Zinc and manganese phosphates are also used to help break in parts subject to wear and to prevent galling. Zinc phosphate is often used with sodium stearate for lubrication in forging processes. It may be applied to a variety of substrates. Main Types of Phosphates The main types of phosphates … [Read more...]

Phosphating at Low Temperatures for Ferrous Metals

Phosphating at ambient temperature and at high temperature both have weaknesses.  Room temperature phosphating produces large amounts of sediment and slime, shows poor wear and corrosion resistance, and can produce fungus.  Phosphating at high temperatures (145-160 degrees F) will result in high energy consumption, as well as greater chemical consumption. Phosphating processes at lower temperatures (110-120 degrees F) has shown the strengths in producing a fast coating forming rate, low energy consumption, manageable sludge beds, and good corrosion resistance. Iron phosphate conversion … [Read more...]