辊套材料的导磁性对铸轧区磁感应强度的影响

Influence of magnetoconductivity of roller shell on magnetic induction in roll casting zone

采用对比实验考察在新型材料辊套和合金钢辊套下铸轧区磁感应强度的差异;根据电磁场理论,研究上述2种辊套材料对铸轧区磁场的衰减和屏蔽效应。研究结果表明:合金钢辊套的相对磁导率为300,是新型辊套材料的300倍;合金钢辊套对磁场既具有衰减作用又具有聚磁效应,衰减作用使铸轧区的磁感应强度减小,聚磁效应使磁感应强度增大;合金钢辊套对磁场的聚磁效应比对磁场的衰减作用强,使铸轧区的磁感应强度增大5%左右。新型材料辊套对磁场只有衰减作用,使铸轧区的磁感应强度降低5%左右。当电磁感应器的励磁电流为10A、励磁频率为13Hz时,在合金钢辊套下比在新型材料辊套下铸轧区的磁感应强度大10%左右。从磁场利用的角度考虑,在电磁场快速铸轧技术中使用合金钢辊套比使用新型材料辊套更好。

By adopting the contrastive experiments, the differences of the magnetic induction in the roll-casting zone were researched in different conditions between the new material roller shells and the alloy steel roller shells. And based on the theory of electromagnetic field, the attenuation and shield effect of the above-mentioned roller shells on the magnetic field were also investigated. The results show that the relative permeability of the alloy steel roller shell is 300, which is 300 times of that of new material roller shell. The alloy steel roller shell attenuates and congregates magnetic field. Attenuation diminishes the magnetic induction in the roll casting zone. However, magnetic congregate effect augments the magnetic induction by centralizing the magnetic field lines around the roll casting zone. Its magnetic congregate effect has an advantage over attenuation in the influence on magnetic field, which increases the magnetic induction by about 5%. In contrast, the new material roller shell only attenuates the magnetic field, which decreases the magnetic induction about by 5%. The magnetic flux density in the roll casting zone under the condition of using alloy steel roller shell is about 10% higher than that under the condition of using the new material one when the exciting current of inductor is 10 A and exciting frequency is 13 Hz. So it is better to use the alloy steel roller shell in the technology of high-speed electromagnetic roll casting in terms of utilizing magnetic field.