| 摘要 |
<p>Provided is a ferrite heat-resistant cast steel having excellent normal-temperature toughness, the composition of which is, by mass ratio, 0.32 to 0.48% of C, 0.85% or less of Si, 2% or less of Mn, 1.5% or less of Ni, 16 to 19.8% of Cr, 3.2 to 5% of Nb such that Nb/C is 9 to 11.5, 0.15% or less of N, 0.002 to 0.2% of S, and a total of 0.8% or less of W and/or Mo, with the balance being Fe and inevitable impurities. The structure is such that a eutectic (d+NbC)phase consisting of a d phase and an Nb carbide (NbC) accounts for 60 to 90% of the surface area. Also provided is an exhaust system component formed from ferrite heat-resistant cast steel.</p> |
