Cu2S and AlN Precipitates in Fe-3%Si-0.5%Cu Steel Produced by Low Slab Reheating Technique

The grain oriented silicon steel containing 3%Si-0.5%Cu was produced by low slab reheating temperature technique. The precipitates were observed during the mainly process such as hot rolling, normalization, primary and secondary recrystallization annealing. The species, size, density and shape of precipitates were identified using TEM technique. The results indicate that Cu2S and AlN are mainly inhibitors which precipitate during hot rolling and normalization respectively. After primary recrystallization annealing the precipitation size of Cu2S is in the range of 30~40nm while the mean size of AlN is ~50nm, which could inhibit grain growth. In addition, the precipitation of MnS is inhibited comparing with the precipitation of Cu2S.