Bending Galvanized Rebar
Hot-dip galvanized reinforcing steel can either be bent prior to
galvanizing or after the galvanized coating has been applied. When
bending prior to galvanizing, it is
recommended that the the minimum finished bend
diameter be as large as possible to avoid strain-age
embrittlement from excessive cold forming of the
steel.
When bending galvanized rebar after the hot-dip galvanizing process,
some cracking or flaking of the galvanized coating at the bend may
occur. The speed of which the article is bent also may affect the
coating integrity. The galvanized coating is best maintained at
slower bend speeds. Some cracking and flaking of the galvanized
coating in the bend area is not cause for rejection. Any flaking
or cracking can be repaired by an acceptable repair method (see Touch-up
& Repair).
Usually when cracking, or flaking, of the coating occurs on the bent
section of the rebar, the outer zinc layer is the only layer that
cracks. Coating thickness measurements will indicate that the
zinc-iron alloy layers are still intact to provide numerous years of
corrosion protection.
