HIGH CARBON HOT/COLD ROLLED STEEL COIL AND MANUFACTUREING METHOD THEREOF

摘要

PURPOSE: A high carbon hot/cold-rolled steel sheet and a manufacturing method thereof are provided to omit a heat treatment process by controlling components and forming fine pearlite in a hot rolling process. CONSTITUTION: A manufacturing method of a high carbon hot/cold-rolled steel sheet is as follows: a step of preparing high carbon steel; a step of manufacturing the steel sheet by hot-rolling the steel in an austenite section over the transformation temperature of Ar3; a step of rapidly cooling the steel sheet at 520-620°C before the phase transformation is started in ROT(Run-Out Table); a step of uniformly maintaining a cooling preservation temperature in which the cooled steel sheet is phase-transformed; and a step of winding the steel sheet at the cooling preservation temperature. [Reference numerals] (AA) Perlite; (BB) Colony; (CC) Layer gap