The presence of shear bands in the deformed material before final annealing is very important for Goss and Cube textures formation in silicon steel [S.C. Paolinelli, M.A. Cunha, J. Magn. Magn. Mater. 255 (2003) pp. 379. [1]; J.T. Park, J.A. Szpunar, Acta Mater., 51 (2003) 3037. [2]]. The increase of the hot-band grain size can increase the number of shear bands, which favor the nucleation of these orientations. In this work, the effect of the hot band grain size variation, promoted by varying the hot rolling finishing temperature, on final structure and magnetic properties was investigated for 3% Si alloy. It was found that the increase of the hot-band grain size increases the occurrence of shear bands and promotes an increase of Z fiber fraction and a reduction of g fiber fraction, improving the magnetic induction. On the other hand, the final grain size is reduced when the hot-band grain size is larger than 190 mm, deteriorating the core loss values in spite of the texture benefits. The reduction of final grain size was explained by the increase of the number of nuclei at the beginning of the recrystallization caused by the increase of shear bands in the deformed material. r
The effect of carbon content on the magnetic ageing index and Vickers hardness evolution on annealed samples of 2%Si non-oriented grain electrical steel was studied. Samples with 40 and 60ppm carbon content were subjected at ageing temperatures of 200 and 225ºC, respectively. During the ageing treatment, the cycle was interrupted on several time intervals in order to obtain the core loss and to determine Vickers hardness. The precipitates were characterized using scanning electron microscope (SEM). Using the software MatCalc, computer simulations of ε-carbide precipitation were performed and compared with experimental data from literature. The results for both carbon contents showed that the maximum hardness value was achieved in shorter time than that to achieve the maximum magnetic ageing, indicating that the critical size of precipitates more harmful to the magnetic properties is larger than the ones that maximize the hardness.
To study the effect of the annealing temperature on the structure and magnetic properties of a 2%Si non-oriented steel cold rolled samples were submitted to final annealing in the temperature range of 540 °C to 980 °C in hydrogen atmosphere. The samples had received cold rolling reduction of 75% to a final thickness of 0.50 mm. Recovery and recrystallization resulted in significant improvement of magnetic properties, with decrease of iron loss (W1.5) and increase of polarisation (J50) and relative permeability (µ1.5). On further grain growth, after recrystallization, there was simultaneous decrease of iron loss, polarisation and relative permeability. Texture evolution on grain growth accounts for the observed decrease of J50 and µ1.5. The beneficial effect of increasing grain size on core loss overcomes the detrimental effect of texture resulting in decrease of W1.5
The evolution of annealing texture of non-oriented grain silicon steel as a function of annealing temperature was investigated from hot rolled samples taken from industrial production. Hot band samples were annealed at 900°C, cold rolled to final thickness of 0.5mm in a single stage cold rolling process or in two stages with intermediate annealing at 900°C, and final annealed in the temperature range from 540°C to 980°C. The results show that the [001]||RD fibre is an important recrystallization texture component, but it may be consumed by further grain growth and become a minor component. The effect of grain growth in the temperature range investigated seems to be that of strengthening the main components at the expenses of the others. The results suggest that to avoid the reduction of the [001]||RD fibre on grain growth a volume fraction ratio between the texture components (111)[112] and (110)[001] close to unity is necessary after recrystallization. This can be obtained under conditions that enhance [001]||RD fibre on recrystallization, such as: strong [111]ND fibre in the deformation texture, large initial grain size and enhanced grain boundary mobility, by proper composition and purity.
The influence of small antimony addition and thermomechanical processing on the magnetic properties of a 3% Si steel was investigated. The samples were processed in the laboratory with 930 1C hot rolling finishing temperature, three different hot band thicknesses, hot band annealing at 1030 1C, cold rolling with three different reductions to 0.35 mm thickness and final annealing at 1030 1C. The results have shown that the best combination of core loss and magnetic induction can be obtained by Sb content of 0.045% and 76% cold rolling reduction, and that Eta/Gamma ratio is higher and grain size larger at this Sb content.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.