NON NORMALIZED STEEL, METHOD FOR PRODUCING THE SAME AND CHASSIS PART FOR VEHICLE

摘要

Disclosed are non-normalized steel which comprises Fe as the main component and which is composed of 0.30-0.50 wt% of C; 0.80-1.20 wt% of Si; 1.30-1.70 wt% of Mn; less than or equal to 0.020 (0 is exclusive) wt% of P; 0.030-0.040 wt% of S; 0.10-0.20 wt% of Cr; 0.02-0.20 wt% of V; 0.01-0.10 wt% of Nb; less than or equal to 0.0030 (0 is exclusive) wt% of B; 0.02-0.05 wt% of Al; 0.0050-0.0200 of wt% N; and other inevitable impurities; a manufacturing method therefor; and a chassis part thereof.