Technical essentials of the new method of electric

Technical knowledge: new method and technical points of oriented electrical steel

[hardware and electromechanical] oriented electrical steel refers to the Cold-rolled electrical steel containing 2.9% - 3.5% Si, with a certain regularity and direction of steel plate crystal structure, which sometimes makes it difficult to pull. It is an indispensable soft magnetic material for the power industry in the transition from glassy state to high elastic state. In production, in order to avoid sticking during annealing, a MgO type isolating agent is generally used, that is, a layer of inorganic material with stable performance is coated on the surface of the steel plate at high temperature. The manufacturing technology of this lithium battery material is at the leading level in China. This method will cause moisture on the surface of the steel plate and deteriorate the magnetic properties of the steel plate. JFE company in Japan has developed a new method without spacer. Technical points:

1. Technical premise:

try to control the content of S and se as low as possible, which is an important premise for realizing continuous final annealing without coating annealing spacer

2. Key points of production:

1) hot rolling of slabs after heating to below 1250 ℃

2) hot rolled plates are annealed at ℃

3) the annealed hot-rolled plate shall be cold rolled twice or more, and an annealing treatment shall be carried out between the two cold rolling. If decarburization treatment is required, the first recrystallization annealing should be carried out in a humid atmosphere; The first recrystallization treatment can be carried out in dry atmosphere without decarburization

4) after the first recrystallization, carry out secondary recrystallization annealing at ℃, and the annealing time must be more than 5h

5) the temperature of continuous final annealing without annealing spacer is in the low temperature range of sexual pair above 1100 ℃, and the annealing time should not exceed 30min (within 10min, it is more conducive to obtain excellent magnetic properties). The annealing atmosphere can be Ar atmosphere, or gases such as H2 and he can be used as the final annealing atmosphere

according to the test results of mm thick oriented electrical steel developed by JFE, the iron loss value (w17/50) of the steel is 0 648w/kg, indicating that the electrical steel has excellent magnetic properties