Patent ID: 8741215

Claim:
A heat-resisting steel for engine valves excellent in high temperature strength, consisting essentially of, in % by mass: C: 0.20 to 0.50%, Si: 1.0% or less, Mn: 5.0% or less, P: 0.1 to 0.5%, Ni: 8.0 to 15.0%, Cr: 16.0 to 25.0%, Mo: 2.0 to 5.0%, Cu: less than 0.3% and more than 0%, Nb: 1.0% or less and more than 0%, W: 8.0% or less and more than 0%, N: 0.02 to 0.2%, B: 0.01% or less, and remnants of Fe and impurities, wherein the heat-resisting steel for engine valves satisfies Formulae below: 442P(%)+12Mo(%)+5W(%)+7Nb(%)+328N(%)+171≧300 Formula (1) −38.13P(%)+1.06Mo(%)+0.13W(%)+9.64Nb(%)+13.52N(%)+4.83≧0.12 Formula (2).