Jun 10, 2016 0 comment

“I know that the zinc layer of both hot dip galvannealed and electro-galvannealed may contain holes. Ref, Galvatech ’95 Conf. Proceedings page 345. How is it that a coating with this type of irregularity does not exhibit outgassing? Do you know the origin of the gasses in hot dip galvanized: steel substrate, zinc layer or boundary layers? What is the size and the distribution in the paint of the air bubbles.”


“The galvanneal process releases the entrapped gasses. Most likely the zinc layer is the origin of the gasses since steel substrates do not exhibit similar problems. The bubble density is proportional to the amount of gas entrapped in the zinc surface; more importantly the distribution of surface defects is also related to the physical characteristics of the paint; i.e., viscosity.”

Was this answer helpful ? Yes / No