Galvanizing flaking off
Galvanizing flaking off
(OP)
We have experienced problems recently with galvanizing flaking off our mild steel plate components. It seems to occur on the plate edges.
This is a new problem to us, but someone has suggested it is because the plates are now laser cut rather than sheared and the sharp laser cut edge is the cause of the problem.
Anyone got any comments, experiences?
This is a new problem to us, but someone has suggested it is because the plates are now laser cut rather than sheared and the sharp laser cut edge is the cause of the problem.
Anyone got any comments, experiences?





RE: Galvanizing flaking off
RE: Galvanizing flaking off
2) Don't know as the platework was done by a sub-contractor who then had it galvanized. But aren't parts degreased, pickled then washed so they are 'clean' prior to immersion in the molten zinc?
RE: Galvanizing flaking off
RE: Galvanizing flaking off
Any comment of the laser cut edge theory??
RE: Galvanizing flaking off
Regards,
Cory
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RE: Galvanizing flaking off
RE: Galvanizing flaking off
Just talked with a guy at the Galvanising Association. Poor adhering of zinc to the edges of laser cut plate is a known problem. It appears more likely to occur with thinner plates (5mm) than thick ones. The zinc at the cut edges can be peeled back like tinfoil.
The cause of the problem is unclear, but suggestions are a tenacious oxide layer, or a localised hardening of the edge caused by the laser cutting.
The only known solution is to grind back the cut edge!
RE: Galvanizing flaking off