TH86034A - Method for producing high carbon cold rolled steel sheet - Google Patents

Abstract

DC60 (25/09/49) Cold rolled high carbon steel sheet offers both excellent formability and excellent uniformity of stiffness in the sheet thickness direction. Was held by a production method with a Hot rolling of steel containing 0.2 to 0.7% carbon by mass. At the finishing temperature of (Ar3 change point - 20 ° C) or higher for hot-rolled plate preparation; Cooling the hot-rolled sheet to a temperature of 650 ° C or lower at a cooling rate from 60 ° C / s or more to less than 120 ° C / s; Coiling of hot rolled sheet after cooling At a curling temperature of 600 degrees Celsius or lower; Cold rolling Hot rolled coiled at a reduction of rolling of 30% or more in order to prepare cold-rolled sheets; And baking, cold rolled sheet At a ductile temperature of 600 ° C or more to the point of transition of Ac1 or below, the selected figure is shown: Figure 1. High carbon cold-rolled ductile iron that offers both excellent formability and Excellent homogeneity of stiffness in the sheet thickness direction. It is held by a step-by-step manufacturing method: hot rolling of steel containing 0.2 to 0.7% carbon by mass. At the finishing temperature of (Ar3 transformation point - 20 ํ C) or higher for hot rolled preparation; To cool the hot rolled sheet to a temperature of 650 ํ C or lower at a cooling rate from 60 ํ C / sec or more to less than 120 ํ C / sec; Coiling of hot rolled sheet after cooling At a curling temperature of 600 ํ C or lower; Cold rolling Hot rolled curl at reduction of ironing at 30% or more, friends prepare cold-rolled sheets; And baking, cold rolled sheet At a baking temperature of 600 ํ C or more to a transformation point Ac1 or lower, the selected figure is shown: Figure 1 .:

Claims (2)

Disclaimer (all) which will not appear on the advertisement page: EDIT 16/02/2017 1. Method for producing high carbon cold rolled steel sheet. It consists of: Hot rolling of steel containing 0.2 or more to 0.7% or less of carbon, 2% or less of silicon, 2% or less of manganese, 0.03% or less of phosphorus, 0.03% or less. Than that of sulfur, 0.08% or less of Sol. Aluminum, 0.01% or less of nitrogen, by mass, and the remainder is iron and its inevitable impurities. At finishing temperature (Ar3 change point - 20 ํ C) or higher for hot-rolled sheet preparation; To cool the hot rolled sheet to a temperature of 550 ํ C or more to 600 ํ C or lower at a cooling rate in the range from 85 ํ C / sec or more to less than 120 ํ C / sec; Hot-rolled coil after cooling at a coiling temperature of 480 ํ C or higher to 550 ํ C or lower; Cold-rolled hot-rolled coiled sheets at a reduction of rolling 30% or more in order to prepare cold-rolled sheets; And cold-rolled sheet annealing at a baking temperature in the range from 600 ํ C or more to Acl transformation point or lower for between 8 h and 80 h to recrystallization and crystallization. Carbide roundness 2. Method for producing high carbon cold rolled steel sheet according to claim 1., where the hot-rolled plate after coiling is annealed. At a baking temperature in the range from 600 ํ C or more to Acl transformation point or lower for between 8 h and 80 h to make carbide spherical. Followed by the use of cold rolling. 3. Method for producing high carbon cold steel coil. According to claim 1 or 2, _ where steel has, added to the above elements, at least one chromium and Molybdenum in the range follows 3.5 mass percent or less of chromium and 0.7% or less of molybdenum, 1.5 percent mass or less of chromium and 0.7 percent mass. Or less of molybdenum ----------------------------- 1. Method for producing high carbon cold rolled steel sheet. The stage consists of: hot rolling of steel containing 0.2 to 0.7% carbon by mass at the finishing temperature of (Ar3 transformation point - 20 ํ C) or higher for hot rolled preparation; To cool the hot-rolled sheet to a temperature of 650 ํ C or less at a cooling rate in the range from 60 ํ C / sec or more to less than 120 ํ C / sec; Hot-rolled coil after cooling to a coiling temperature of 600 ํ C or lower; Cold-rolled, hot-rolled coiled sheets at 30% or more reduction in extrusion, friends prepare cold-rolled sheets; And annealing of cold rolled sheets at a temperature of 600 ํ C or higher to the Ac1 or lower transition point. 2. Method for producing high carbon cold rolled steel coil according to Clause 1. Where The cooling process cools the hot rolled sheet. To a temperature of 600 ํ C or lower at a cooling rate in the range from 80 ํ C / s or more to less than 120 ํ C / s, and the curl step is coiled at 550 ํ C or less. Method for producing high carbon cold rolled steel sheets According to the claim 1. or clause 2. Where the sheet is hot rolled after coiling It is annealed at a baking temperature in the range from 600 ํ C or higher to the transformation point Ac1 or lower, followed by cold rolling.