| 摘要 |
<p>Disclosed is a spring steel having a high strength of not less than 1900 MPa while exhibiting excellent brittle facture resistance. Also disclosed is a method for producing such a spring steel. Specifically disclosed is a high-strength spring steel containing, in mass%, 0.4-0.6% of C, 1.4-3.0% of Si, 0.1-1.0% of Mn, 0.2-2.5% of Cr, not more than 0.025% of P, not more than 0.025% of S, not more than 0.006% of N, not more than 0.1% of Al and not more than 0.0030% of O as basic components. In this spring steel, the solid solution C content is not more than 0.15%, the Cr content contained as Cr-containing deposit is not more than 0.10%, and the TS value represented by the formula below is not less than 24.8%. Regarding the constitutional structure, the spring steel has a prior austenite grain size of not more than 10 mum. In the following formula, [X] represents the mass% of element X. TS = 28.5*[C] + 4.9*[Si] + 0.5*[Mn] + 2.5*[Cr] + 1.7*[V] +3.7*[Mo]</p> |
