Abstract
The magnetic properties of non-oriented electrical steel, widely used in electric machines, are closely related to the grain size and texture of the material. How to control the evolution of grain size and texture through processing in order to improve the magnetic properties is the research focus of this article. Therefore, the complete process chain of a non-oriented electrical steel with 3.2 wt.-% Si was studied with regard to hot rolling, cold rolling, and final annealing on laboratory scale. Through a comprehensive analysis of the process chain, the influence of important process parameters on the grain size and texture evolution as well as the magnetic properties was determined. It was found that furnace cooling after the last hot rolling pass led to a fully recrystallized grain structure with the favorable ND-rotated-cube component, and a large portion of this component was retained in the thin strip after cold rolling, resulting in a texture with a low γ-fiber and a high ND-cube component after final annealing at moderate to high temperatures. These promising results on a laboratory scale can be regarded as an effective way to control the processing on an industrial scale, to finally tailor the magnetic properties of non-oriented electrical steel according to their final application.
Highlights
Non-oriented (NO) electrical steel is widely used to make stators and rotors of electric machines like generators and motors
For each of these three steps, experimental investigations were carried out to identify the influence of the process parameters introduced in detail above on both the microstructure in terms of grain size distribution and the texture in terms of orientation distribution function (ODF)
A low finishing temperature in combination with water quenching after hot rolling led to a deformed state with small grains near the surface and a banded structure with flat elongated grains in the mid layer, whereas a furnace cooling after hot rolling resulted in a fully recrystallized, more homogeneous microstructure across the strip thickness with a mean grain size of
Summary
Non-oriented (NO) electrical steel is widely used to make stators and rotors of electric machines like generators and motors. Their overall efficiency and performance depend strongly on the quality of the NO electrical steel. High quality NO electrical steel provides good magnetic properties, especially easy magnetization and low magnetic losses. These magnetic properties are inextricably linked to the grain size and crystallographic texture of the material. I.e., center lines of continuous orientation tubes in Euler space are usually used to describe these characteristic texture components [2]. To quantify the magnetic quality of a texture, Kestens et al [6] proposed the A-parameter, where the angle Aθ (g) is the minimum angle
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
