Patent ID: 8900381

Claim:
A spring steel comprising, by mass, 1.2% or less carbon (C); 0.1% to 2% manganese (Mn); 0.2% to 3% silicon (Si); 0.0003% to 0.005% aluminum (Al); 0.03 to 8 ppm lithium (Li); 30 ppm or less (excluding 0 ppm) calcium (Ca); and 28 ppm or less (excluding 0 ppm) magnesium (Mg), wherein the steel contains oxide inclusions satisfying the following conditions (1) to (3) in a number of 1×10 4 or more per square millimeter: (1) the oxide inclusions each contain a total of 80 percent by mass or more of Al 2 O 3 and SiO 2 based on the inclusion composition excluding Li 2 O; (2) the oxide inclusions each have a ratio by mass of Al 2 O 3 to SiO 2 of from 1:4 to 2:3; and (3) the oxide inclusions each contain lithium (Li), and wherein the oxide inclusions are Li 2 O.Al 2 O 3 .4SiO 2 crystals.