Vacuum Degreasers and Aqueous Solutions
Published

Adhesion on Galvannealed Material

What causes paint adhesion problems on galvanneal material?

Share

Q. We are having paint adhesion problem on galvanneal material. We have a degreasing facility with a seven-tank process. —A.K.

A. Zinc coated steels can be notoriously difficult to achieve good paint adhesion. Some of the problems are related to the mill coatings and oil that are applied to the galvanneal to ensure they do not oxidize. These can be very tenacious, particularly if shipping from overseas and needing the associated extended corrosion resistance.

Additionally, the zinc coating of a simple galvanized can be one of the most difficult of the zinc coated steels to get good paint adhesion. The galvannealed variety essentially takes the hot dip galvanized steel and bakes it, which will form a zinc-iron alloy that significantly improves the paint adhesion while maintaining the material corrosion resistance.

It is unclear what is involved in your seven-tank cleaning system, but time, temperature, cleaner concentration and agitation are the most important factors to control to maximize the potential of your cleaning system. As mentioned, the lubricants applied at some of the mills can be particularly difficult to remove. I would recommend increasing the time, temperature and cleaner concentration in an effort to better remove the contaminants. 

Related Content

  • Pretreatment of Black Oxide

    Having issues achieving a consistent color with the application of black oxide? Start by looking at your pretreatment. Connor Callais of Hubbard-Hall offers advice for troubleshooting your black oxide process.

  • Vacuum Degreaser Cleans Up a Messy Situation

    By replacing its immersion parts washer with a vacuum degreasing system, this machine shop is much more efficient, saving the company money, man hours and the health of the operators.

  • Advantages to Pumped Eductor Agitation

    Not all agitation methods are created equally. Pumped agitation with eductor nozzles can improve process tanks and quickly show a reduction in operating costs while keeping staff safe, following environmental legislation and preventing pollution.

vacuum vapor degreasers
Cleaning questions ask Kyzen
Pickelx one step metal prep
high-performance systems for efficient parts cleaning
Precision Cleaning Solvents
Cleaning Technologies Group
Echoflex modular ultrasonic cleaning machines
Heatmax Heaters ad with immersion heaters
Vacuum Degreasers and Aqueous Solutions