| 摘要 |
A spring steel includes a predetermined chemical composition and a composite inclusion having a maximum diameter of 2 µm or more that TiN is adhered to an inclusion containing REM, O and Al, in which the number of the composite inclusion is 0.004 pieces/mm 2 to 10 pieces/mm 2 , the maximum diameter of the composite inclusion is 40µm or less, the sum of the number density of an alumina cluster having the maximum diameter of 10 µm or more, MnS having the maximum diameter of 10 µm or more and TiN having the maximum diameter of 1 µm to 10 pieces/mm 2 . |
