The invention discloses a control method for improving the surface wettability of ultrahigh-strength steel, and belongs to the technical field of
metallurgy. The method comprises the steps that S1, a closed area is designed in a certain temperature interval of the annealing furnace, S2, O2-containing gas is sprayed to the surface of
strip steel in the closed area of the annealing furnace, and the concentration of O2 in the
atmosphere in the closed area is controlled; s3, when the
strip steel enters the closed area of the annealing furnace with the strong oxidizing
atmosphere, the surface of the
strip steel is rapidly pre-oxidized, and a layer of Fe
oxide with the uniform thickness is formed; s4, after the strip steel penetrates through the pre-oxidation closed area, the strip steel enters an annealing reduction area containing H2
atmosphere, Fe
oxide on the surface is gradually reduced into
sponge iron, other
alloy element oxides are covered below the
sponge iron, an
internal oxidation phenomenon is generated, the
sponge iron on the surface of the strip steel and
zinc liquid provide good wettability, and the surface of the strip steel and the
zinc liquid are not prone to oxidation; therefore, the surface wettability of the ultrahigh-strength steel in the hot dipping process is improved, and an ultrahigh-strength steel product with good surface quality is produced.