Maximum dry-off oven temperatures for phosphate coatings
We are having a dispute in our company as to the maximum temperature (and time) we can have in our dry-off oven without dewatering our lightweight iron phosphate coatings produced in our 6 stage spray washer. We also have another line that uses zinc phosphate for automotive parts, and have disagreed as to the maximum temperature (and time) for that dry-off oven as well - before dewatering of the coating occurs.
Does anyone have a technical article that they can refer me to so I can read it for myself, or, if not, let me know by response to this inquiry in the usual written fashion.
Many Thanks,Tom Meyer
- Milwaukee, Wisconsin, USA
Stoving times are very flexible. At temps above 150 deg C for 20+ mins 2 molecules of water will be driven off from zinc phos. This is NOT detrimental in any way. Above 250 deg C complete dehydration will occur and this will most definitely adversely affect performance. Lightweight iron will be less affected. In short you could use powder cure temps for drying and not suffer!Roger Bridger
- Croydon, UK
This public forum has 60,000 threads. If you have a question in mind which seems off topic to this thread, you might prefer to Search the Site