| 摘要 |
Provided is a train axle having an exceptional fatigue limit and fatigue notch factor. The train axle according to the present embodiment has a chemical composition that contains, expressed in wt%, C: 0.20-0.35%, Si: 0.20-0.65%, Mn: 0.40-1.20%, P: 0.020% or less, S: 0.020% or less, Cu: 0-0.30%, Ni: 0-0.30%, Cr: 0-0.30%, Mo: 0-0.08%, Al: 0-0.100%, N: 0.0200% or less, V: 0-0.060%, and Ti: 0-0.020%, the remainder being Fe and impurities, and that satisfies expression (1) and expression (2). 0.58 ≦ C + Si/8 + Mn/5 + Cu/10 + Cr/4 + V ≦ 0.67 (1) Si + 0.9Cr ≧ 0.50 (2). Here, the content of the corresponding element (in wt%) has been substituted for element symbols in expression (1) and expression (2). |
