Influence of Inclusions on Magnetic Properties of Al-Killed Non-oriented Silicon Steels

The influence of inclusions and microstructure on magnetic properties was investigated in calcium(Ca)-treated non-oriented silicon steels. The total number density of inclusions was reduced due to the removal of low melt point and calcium sulfide (CaS)-bearing inclusions. Inclusions containing manganese sulfide (MnS) decreased, while those with aluminum nitride (AlN) increased. The segregation concentration of Mn, S, Al, and N during the solidification process was calculated based on a simple microsegregation model. The results showed that the Ca treatment modulated the precipitation characteristics of MnS and AlN. An increase in the grain size was observed accompanied by a reduced number density of precipitates. The density of gamma-fiber texture increased, while that of the eta-fiber texture decreased. The core loss and magnetic induction decreased by 10.06% and 3.50%, respectively. These results indicated that an appropriate Ca treatment during the refining process could effectively modify the inclusions and reduce the core loss.

Automated summary

The influence of inclusions and microstructure on magnetic properties in calcium-treated non-oriented silicon steels was investigated. It was found that the calcium treatment effectively modified the inclusions and reduced the core loss. The precipitation characteristics of certain inclusions were also modulated, resulting in changes in grain size and texture density.