A hot forged non-heat treated steel for induction hardening, comprising by
mass percent, C: 0.35 to 0.45%, Si: 0.20 to 0.60%, Mn: 0.40 to 0.80%, S:
0.040 to 0.070%, Cr: 0.10 to 0.40%, Ti: 0.020 to 0.100%, Ca: 0.0005 to
0.0050%, B: 0.0005 to 0.0030%, O: 0.0015 to 0.0050%, Mo: 0 to 0.05%, P:
0.025% or less, V: 0.03% or less, Al: 0.009% or less and N: 0.0100% or
less, and the balance being Fe and impurities, with
Fn1=C+(Si/10)+(Mn/5)+(5Cr/22)+1.65V-(5/7S)+1.51.times.(Ti-3.4N).ltoreq.0.-
63, Ca/O.ltoreq.1.0, and
25.9.times.Fn1+27.5.times.(Ti-3.4N)-7.9.gtoreq.5.7, has more excellence
in the machinability than a conventional steel and also has fatigue
strength equal to or more than that of a conventional steel, while using
the steel product in a hot forged state as a starting material.