Production process of Cold Rolled Grain Oriented Electrical Steel Sheet

- Jan 25, 2019-

It is well known that thin slab casters are in principle particularly suitable for the production of magnetic steel sheets, since beneficial temperature control can be carried out for on-line processing of thin sheets. When cold-rolled grain-oriented electrical steel sheets are produced, the molten metal is first formed into a thin steel sheet having a thickness of 30-140 mm, and the hot-rolled steel strip is annealed at a temperature of 950-1150 ° C for 30-600 seconds, followed by a deformation strain of 50-85%. It becomes a cold-rolled strip and obtains a cold-rolled grain-oriented electrical steel sheet having ideal magnetic properties.


In order to be able to take advantage of the casting/rolling process, as a result of producing a cold-rolled grain-oriented electrical steel sheet using a thin plate as a starting material, the first forming step is carried out at a temperature lower than 1150 ° C and the strain strain is at least 20% from 40- The 8 mm intermediate thickness of the rolled strip is reduced to a rolling temperature below 1000 ° C in the up to two-step subsequent forming rolling by the high pressure inter-stand cooling device. This avoids the formation of the strip in a temperature range of around 1000 ° C, which is important for its ductility.


The production of cold-rolled grain-oriented electrical steel sheets also requires a highly precise adjustment of the target chemical composition, ie the individual components must be adjusted very precisely in coordination with each other, depending on the absolute content chosen, the restrictions on some components are very strict. The treatment in the ladle furnace reaches its limit. In this respect, significantly better conditions can be achieved by using vacuum equipment.