The effects of normalization on different texture components and magnetic properties in G50W600 nonoriented electrical steel are studied by electron backscatter diffraction (EBSD). The results show that normalization can coarsen surface {110}‐oriented grains and recrystallized rotated cube or {114}<481>‐oriented grains in the center. Moreover, the highest texture intensity change from original rotated cube texture to the {114}<481> texture with the increase of normalization temperature. Just after the completion of recrystallization in final sheets corresponding to hot‐rolled samples, {111}<112> is the main texture component, while that in final sheets corresponding to normalized samples is {114}<481>. The final sheets normalized at 920 and 980 °C have a higher iron loss and higher magnetic induction than the final sheets corresponding to hot‐rolled samples, which is caused by the fact that normalized samples show finer final grain size, higher volume faction of {100} and {110}, and lower volume fraction of γ‐fiber than hot‐rolled samples. With the increasing of annealing temperature and time, the magnetic induction and iron loss of normalized samples decrease. Furthermore, the final sheets normalized at 940 °C have the best magnetic properties. During final high temperature annealing, the non γ‐fiber oriented grains show a higher growth ability than γ‐fiber oriented grains.

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The cast slab of low grades non-oriented electrical steels experiences twice diffusional solid phase transformation and demonstrates the features of strong morphological memory referring to columnar structure and texture memory referring to the preferred < 100 > texture at room temperature. In this paper, electron backscatter diffraction (EBSD), quasi-insitu observation of heating samples, and dilatometry are used to study and analyze the two kinds of memory phenomena. The results show that the cast slab consists of about 70% coarse columnar grains and 30% small equiaxed grains. Many small equiaxed grains show Σ3 misorientations with columnar grains indicating K-S orientation relationship obeyed during phase transformation. Coarse columnar grains show a typical < 100 > ||growing axis orientation which is the same as solidified columnar grains. The quasi-insitu observation shows that transformation of columnar grained ferrite to austenite is very sluggish and columnar grained ferrite can still be seen even at a superheating degree of 176°C for 1 hour. Dilatometry measurement indicates that the starting transformation temperatures for a columnar-grain-dominant sample and a small-equiaxed-grain-dominant sample are similar, whereas their transformation extents are quite different with columnar grained sample showing a low dilatational amount due to insufficient transformation. It is most likely that the coarse columnar grains in cast slab are retained and untransformed high temperature δ-ferrite are not subjected to twice complete transformations. These retaining columnar grains in low grades of electrical steels can be used to improve magnetic properties through optimizing processing parameters.

The steel slag based ceramics (SSBC) with different contents of magnesium ions were prepared by conventional sintering process. The variations of linear shrinkage, water absorption, bulk density and apparent porosity of the samples fired at different temperatures from 1130 to 1210uC were measured. The phase formation and microstructure of final ceramics were observed by Xray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that increasing magnesium ions content in SSBC does not change the crystal phases but increases the sintering temperature. The final phases in SSBC are pyroxenes including augite and diopside. Crystalline phases in SSBC form before densification. Substitution of Fe 2z for Mg 2z in phases would increase amount of Fe 2z in crystal, but decreases the amount in liquid, which is the main factor of the sintering temperature increase. Good degrees of densification and high crystallinity of ceramics show good mechanical properties.

The effects of various initial structures and heating and cooling rates on the columnar‐grained transformation temperature are studied by a thermal dilatometer and electron backscatter diffraction. The results show that deformation can reduce the thermal hysteresis more effectively than decrease the heating rate, and the phase transformation hysteresis of the deformed sample is the smallest during heating, followed by the columnar‐grained sample with a slow heating rate, whereas the columnar‐grained sample with a fast heating rate has the largest phase transformation hysteresis. Moreover, the dilatational amount changes greatly with cooling rate. The coarse columnar grains can severely restrain dilatation. The smaller dilatational amount is related to the incomplete phase transformation of the columnar grains and also related to the suppression of the dilatational amount of the small grains by the surrounding columnar grains. In contrast, the largest dilatational amount is caused by the relatively sufficient phase transformation. In addition, the changes of the transformation temperature and the dilatational amount are mainly induced by the grain size effect and the inhomogeneity of the structures, but {100} texture can affect the uniformity of grain size.

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