The Formation Mechanism Of {100} Texture During Solidification Process Of Non-oriented Silicon Steel

In this paper,the formation mechanism of {100} grains during CET process of 1.315% ~ 4.568% Si-0.141% ~ 0.506% Al non-oriented silicon steel has been systematically studied by directional solidification,dendritic erosion technology,Factsage thermodynamic calculation software,EPM,LEO-1450 SEM and HKL-EBSD.The geometry,orientation and typical solute enrichment characteristics of dendrites before and after CET process of non-oriented silicon steel with different Si and Al contents and solidification rates are analyzed.The influence mechanism of heat and mass transfer behavior on {100} equiaxed crystal formation during CET transformation was discussed.The main results are as follows:The results show that when the solidification rates are 10?m/s,35?m/s and 80?m/s,the solid-liquid interface of 1.315%~4.568%Si-0.141%~0.506%Al non-oriented silicon steel is cell crystal,cystiform dentrite,dendrite respectively.And the spacing of the primary cell/dendrite and secondary dendrite of non-oriented silicon steel decreased as a whole with the increase of Si content or Al content.With the increase of solidification rate,the spacing of the primary cell/dendrite and secondary dendrite of non-oriented silicon steel gradually decrease under the same content of Si and Al.The different contents of Si and Al and solidification rates,the segregation of Si on the solid-liquid interface of non-oriented silicon steel is the most obvious.With the increase of solidification rate,the segregation of Si on the solid-liquid interface of nonoriented silicon steel firstly increases and then gradually decreases,Al is not easy to be enriched at the solid-liquid interface,which is a difficult the element of segregation.The content of Si and Al on the cell/dendrite at the solid-liquid interface is not uniform and is obviously higher than that at other positions.With the increase of solidification rate and Si content in steel,the Si is point-like and non-uniform distribution on the primary dendrite of the solid-liquid interface of non-oriented silicon steel,and is easier to precipitate on the primary and secondary dendrites.With the increase of solidification rate and Al content in steel,the more AlN-MnS and AlN appear near the solid-liquid interface of non-oriented silicon steel,the smaller their size is.When the content of Si is less than 1.3% and the content of Al is less than 0.51%,???+??? or ???+?????+??? will only occur at room temperature.When the content of Si is more than 2.28%,no matter how much the content of Al in steel,? transformation will only occur at room temperature.When the solidification rate increases from 10?m/s to 80?m/s,it is easier to form columnar crystals with <100> crystal orientation at the solid-liquid interface for nonoriented silicon steel.When Si content in steel increases from 1.320% to 4.568%,the solid-liquid interface of non-oriented silicon steel changes from a plurality of elongated <100> crystal grains to a single coarse <100> crystal grain,and then to a plurality of grains with different crystal orientations.As the Al content in steel increases from 0.141% to 0.506%,the grain at the solid-liquid interface of non-oriented silicon steel gradually moves to <100>crystal orientation nucleation and grows up.The texture of the solidliquid interface of non-oriented silicon steel with different Si and Al contents is mainly {110}<100> and {100}<100> texture,and with the increase of Si and Al contents,the strength of Goss texture at the solid-liquid interface gradually weakens and the {100}<100> texture gradually strengthens.