To improve lubricatability and degreasability by dispersingly sticking Teflon particles in a specified sticking amount on the surface of the alloyed molten zinc-plated steel.
When the steel is formed under pressure, Teflon particles are inserted between the surfaces of the steel and a metal mold so as to enhance lubricatability. A sticking amount of the Teflon particles is controlled to be 0.1-2.0 g/m2. The particles are stuck in a dispersed state without forming coating film, thereby the increase in electrical resistance between the plated surface and a welding electrode can be prevented in the welding process and the lowering of the welding workability can be suppressed and, further, the Teflon particles can be easily disconnected in the degreasing process and the lowering of degreasability is prevented. The shape of the Teflon particles is preferably spherical. As a method for sticking the Teflon particles on the plated steel surface, roll-coating or spray coating of the surface of the steel using an aq. solution containing water-dispersible Teflon resin or the method comprising, after immersing in the solution, subjecting the surface to linger-roll is cited.
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