The invention provides a VCI (Vapor
Corrosion Inhibitor)
powder bimetallic
coating for steel structure surface protection and a preparation method thereof. The ofpowder bimetallic
coating comprises the following components in parts by weight: a binder, a filler, a VCI vapor
corrosion inhibitor and an auxiliary, wherein the binder comprises 15-25 parts of powdered
epoxy resin, 15-25 parts of powdered
polyester resin, 5-15 parts of
polytetrafluoroethylene resin, and 5-15 parts of organic
silicon resin; the filler comprises 30-60 parts of flake
zinc powder, 1-5 parts of flake aluminum
powder, 5-10 parts of aluminum triphosphate, and 5-10 parts of
zinc phosphate; the auxiliary is selected from one or more of a flatting agent, a conductive agent, a degassing agent and a light stabilizer; the
mass ratio of the binder to the filler is 3:1 to 1:2.5; the
mass of the VCI vapor
corrosion inhibitor is 5-10% of the total
mass of the binder and the filler; the mass of the auxiliary is 2-10% of the total mass of the binder and the filler. The
coating plays a good shielding role as a powdered coating, further plays a
cathode protection role as a common
zinc-rich coating, and meanwhile takes a
corrosion inhibition effect as the VCI vapor
corrosion inhibitor, so as to achieve the excellent protection effect for the
metal binder. In addition, the powdered coating disclosed by the invention is prepared by mixing different weather-resistant resins, so that the powdered coating has better
weather resistance than the common powdered coating.