Estimation of elastic modulus anisotropy in grain-oriented electrical steel using EBSD and DMA methods

Grain-oriented electrical steel (GOES) is characterized by a strong crystallographic texture, which is crucial for its magnetic properties. However, this texture also induces significant anisotropy in its elastic characteristics, which is less studied but important for manufacturing and application. This work investigates the anisotropy of the elastic modulus in GOES at different stages of its production — specifically after the first cold rolling (CR1), after subsequent decarburization−recrystallization annealing (DRA), and after the second cold rolling (CR2). The study employs a combined approach using Electron Backscatter Diffraction (EBSD) for texture analysis and Dynamic Mechanical Analysis (DMA) for direct measurement of storage modulus. Using the EBSD analysis the evolution of the crystallographic texture across the manufacturing stages was studied. The key texture components were qualified and quantified by 20° deviation of standard crystallographic directions <100>, <110> and <111> from CR axes: RD, TD and ND. These data were compared to the spatial maps of Young’s modulus, showing a uniform distribution in the rolling direction (RD) and the greatest dispersion of values in the normal direction (ND) for all processing stages. The maximum modulus values were consistently observed in the transverse direction (TD). A comparative analysis demonstrated a correlation between the elastic moduli values obtained via EBSD calculations and direct DMA measurements. A more significant divergence was noted for the thinner CR2 sheet (0.27 mm), which is attributed to the specific stress state during three-point bending in DMA, which amplifies the contribution of the near-surface layers.

1. Russian Science Foundation - 25-19-00683