Interfacial Phenomena and Inclusion Formation at Early Melting Stages of Lanthanum Ferroalloys in a Non-Oriented Electrical Steel

The dissolution behavior of lanthanum ferroalloy in a non-oriented electrical steel was investigated using a quartz sampler by controlling the contact time between the ferroalloy and molten steel. As the contact time increased, the network microstructure of the lanthanum was continuously destroyed and migrated towards the molten steel. The dissolved lanthanum reacted with the dissolved elements in the steel including Si, As, P and S. The formation sequence of inclusions was La-S → La-P-(As) → La-Si.