The temperature of the three phase EI silicon steel lamination should not be too high when it is annealed. If it is used too high, it will directly affect its insulating coating or bond the laminate. Generally, the temperature of the silicon steel sheet is made. It is indicated that the temperature of the generally oriented silicon steel sheet is about 800 degrees, the annealing temperature of the non-oriented silicon steel sheet is about 700 degrees, and the protective atmosphere in the furnace is strictly controlled to be an oxidizing atmosphere during annealing.
The three phase EI silicon steel lamination is based on the principle that the core insulation sheet is not oxidized, non-carburized and the surface insulation coating of the electrical steel strip (silicon steel sheet) is not significantly deteriorated. It is preferable to use a hydrogen-nitrogen mixed gas containing 2-10% of hydrogen. Adding a small amount of hydrogen ensures that the core sheet does not oxidize. The dew point in the shielding gas should generally be below 0 °C.
The three phase EI silicon steel lamination generates qualified silicon steel sheets during operation, which has certain requirements on equipment and process, and reduces the procurement cost to the minimum while ensuring the quality.
Analysis of Process Characteristics of Three Phase EI Silicon Steel Lamination with Different Silicon Contents
The use of silicon steel sheets with different silicon contents in processing and use is generally the same:
1, [Si]> 2% must be electromagnetically stirred
2. If [Si]>2%, if a cold rolling process is used, it must be treated normally and then pickled.
3, [Si]> 2% due to large deformation resistance, often used 20-roll mill for cold rolling
4. When [Si]>3% or [Si]+[Al]≥3.5%, it must be subjected to secondary cold rolling, and the first cold rolling should be preheated to 100~150°C.