|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||Characterization of Minerals, Metals and Materials
||Precipitate Characterization and Evolution in Grain Oriented Electrical Steel During High Temperature Coil Annealing
||Xukai Zhang, Jamo Momand, Stefan Melzer, Winfried Kranendonk, Gert H. ten Brink, Bart J. Kooi
|On-Site Speaker (Planned)
Precipitates in grain oriented electrical steel (GOES) are crucial for achieving the extraordinary microstructure with sharp Goss texture required for transformer cores with ultra-low losses. In this work, decarburized and nitrided GOES samples were annealed to different temperatures during high temperature coil annealing. Transmission electron microscopy (TEM) investigations show that three types of precipitates are present in GOES. Precipitates were investigated with high resolution TEM, high angle annual dark field (HAADF) scanning TEM and energy dispersive X-ray spectrometry elemental mapping. Two types of areas with high and low number density of intermediate-sized (Al,Si)N precipitates were observed with HAADF-STEM within an SEM, using an image-stitching function. The precipitate size evolution in both areas was separately assessed quantitatively. This new technique not only guarantees high resolution of the image, but also a large area, which is essential for statistical analysis of nanoscale precipitates with low number density.