Steel for induction hardening, roughly shaped material for induction hardening, producing method thereof, and induction hardening steel part

摘要

A steel for an induction hardening including, by mass %, C: more than 0.75% to 1.20%, Si: 0.002 to 3.00%, Mn: 0.20 to 2.00%, S: 0.002 to 0.100%, Al: more than 0.050% to 3.00%, P: limited to 0.050% or less, N: limited to 0.0200% or less, O: limited to: 0.0030% or less, and the balance composing of iron and unavoidable impurities, wherein an Al content and a N content satisfy, by mass %, Al−(27/14)×N>0.050%.

主权项

1. A roughly shaped material for an induction hardening comprising, by mass %,
C: more than 0.75% to 1.20%, Si: 0.002 to 3.00%, Mn: 0.20 to 2.00%, S: 0.002 to 0.100%, Al: more than 0.050% to 3.00%, P: limited to 0.050% or less, N: limited to 0.0200% or less, O: limited to 0.0030% or less, at least one of
V: 0.005 to less than 0.20%,Nb: 0.005 to 0.10%, andTi: 0.005 to 0.10%, and the balance of iron and unavoidable impurities, wherein an Al content and a N content, by mass %, satisfy Al−(27/14)×N>0.050%, and wherein the roughly shaped material has a number of graphite grains with an average grain size of 0.5 μm or more, which is included in the roughly shaped material for induction hardening is 40 pieces/mm2 or less.