High-strength spring steel having excellent corrosion resistance

A high-strength spring steel having excellent corrosion resistance, suitable for use as steel for a coil spring of a vehicle suspension, the high-strength spring steel comprising:

• 0.4 to 0.9 wt % of Carbon (C), 0.9 to 2.3 wt % of Silicon (Si), 0.5 to 1.2 wt % of Manganese (Mn), 0.6 to 1.5 wt % of Chromium (Cr), 0.01 to 0.5 wt % of Molybdenum (Mo), 0.01 to 0.9 wt % of Nickel (Ni), 0.5 wt % or less (excluding 0 wt %) of Vanadium (V), 0.5 wt % or less (excluding 0 wt %) of Niobium (Nb), 0.3 wt % or less (excluding 0 wt %) of Titanium (Ti), 1.0 wt % or less (excluding 0 wt %) of Cobalt (Co), 0.1 wt % or less (excluding 0 wt %) of Boron (B), 0.3 wt % or less (excluding 0 wt %) of Tungsten (W), 0.3 wt % or less (excluding 0 wt %) of Copper (Cu), 0.3 wt % or less (excluding 0 wt %) of Aluminum (Al), 0.03 wt % or less (excluding 0 wt %) of Nitrogen (N), 0.003 wt % or less (excluding 0 wt %) of Oxygen (O), and a remainder of Iron (Fe) and inevitable impurities.