| 摘要 |
<p>Disclosed are a carbon steel and a method for manufacturing the carbon steel capable of ensuring excellent mechanical property by making a process heat treatment structure when a hot-rolled coil is manufactured by controlling an alloying element and a process condition. According to the present invention, the method for manufacturing the carbon steel includes: a step (a) of reheating, at a slab reheating temperature (SRT) of 1150 to 1250°C, a steel slab which consists of 0.30 to 0.40 wt% of carbon (C), 0.15 to 0.35 wt% of silicon (Si), 0.6 to 0.8 wt% of manganese (Mn), 0.025 wt% or less of phosphorus (P), 0.005 wt% or less of sulfur (S), 0.025 to 0.040 wt% of niobium (Nb), 0.006 wt% or less of nitrogen (N), remainder iron (Fe) and inevitable impurities; a step (b) of hot-rolling the reheated steel from a single phase austenite section to a eutectoid transformation temperature section; and a step (c) of cooling the hot-rolled steel up to a coiling temperature of 550 to 600°C and winding the hot-rolled steel.</p> |
