To provide a steel sheet to be enameled, which is highly strengthened when baked after being enameled, without deteriorating formability and enameling properties, and to provide an enameled and baked steel sheet.
The steel sheet to be enamelled includes, by mass%, 0.0040% or less C and 0.6-8.0% Cu. The enamelled and baked steel sheet has crystal grains with a mean size of 5-50 μm, and a metallic phase consisting of Cu with an average diameter of 0.20 μm or less and with a number density of 0.2 pieces/μm3 or more. The method for manufacturing the enamelled and baked steel sheet comprises controlling a holding time at a temperature of 450 to 700°C in a cooling process mainly after hot-rolling and annealing steps in a process of manufacturing the steel sheet, and further in a cooling process after baking after forming the steel sheet, to form the metallic phase consisting mainly of Cu in the steel sheet.
Jun Tsuruta
Hiroshi Kamematsu
Masaya Nishiyama
Next Patent: CASSETTE, THIN FILM DEPOSITION SYSTEM, AND THIN FILM DEPOSITION METHOD