Method for the manufacture of formable steel strip

Method for the manufacture of formable steel strip having a thickness between 0.5 and 1.5 mm characterised by the following process steps which are performed sequentially in a continuous process:

• (a) in a continuous casting machine forming liquid steel into a hot slab having a thickness of less than 100 mm,
• (b) hot rolling the hot slab from step (a), in the austenitic region and below 1100.degree. C., to form strip having a thickness of between 2 and 5 mm,
• (c) cooling the strip from step (b) to a temperature between 400.degree. C. and 600.degree. C.,
• (d) rolling the cooled strip from step (c) at said temperature between 400.degree. C. and 600.degree. C. with a thickness reduction of at least 25% at a rolling speed not more than 1000 m/min.
• (e) subjecting the rolled strip from step (d), to recrystallizing annealing at above 620.degree. C. for at least 0.1 second, and
• (f) coiling the rolled strip from step (e).

Method for the manufacture of formable steel strip having a thickness between 0.5 and 1.5 mm characterised by the following process steps which are performed sequentially in a continuous process:

• (a) in a continuous casting machine forming liquid steel into a hot slab having a thickness of less than 100 mm,
• (b) hot rolling the hot slab from step (a), in the austenitic region and below 1100.degree. C., to form strip having a thickness of between 2 and 5 mm,
• (c) cooling the strip from step (b) to a temperature between 650.degree. C. and the temperature T.sub.t at which 75% of the steel
• (d) is converted to ferrite, rolling the cooled strip from step (c) at said temperature between 650.degree. C. and T.sub.t with a thickness reduction of at least 25% at a rolling speed not more than 1000 m/min.
• (e) coiling the rolled strip from step (d) without reheating after step (d).