Doctoral Dissertations

Keywords and Phrases

Electrical steel; Non-oriented electrical steel; twin roll thin strip casting

Abstract

"In this study, a method to cast non-oriented (NGO) electrical steel with conditions of an industrial twin roll thin strip casting (TRSC) process was investigated. A novel vacuum assisted fast cooling (VA) sampling method was developed to produce 2 mm thick strip simulating conditions of an industrial TRSC process. The effects of solidification cooling rate, hot rolling deformation, and annealing time on inclusion distribution, magnetic properties, grain growth, and texture evolution of 3.4 wt.% Si NGO electrical steel with different carbon and sulfur (C&S) levels were analyzed. Samples were thermo-mechanically treated which simulated an industrial TRSC process. After a long time, batch annealing, low C&S 25% and 47% hot rolled (HR) samples met the target magnetic properties for the 35W250 NGO electrical steel in GB/T 2521.1 (2.50 W/kg for P1.5/50).

Under each C&S level, more small inclusions (in the range 0.15-1.0 μm) were observed in the high solidification cooling rate sample, which caused a negative effect on grain growth and magnetic properties. With the decrease of C&S level, the final grain size decreased, and the magnetic properties improved. This influence was caused by fewer inclusions and less phase transformation during the annealing process. The increase of HR deformation not only increased the final grain size, but also improved the magnetic properties. The texture evolution during the batch annealing process could be divided into different steps. A model for core loss is presented and used to explain the core loss results"--Abstract, p. iv

Advisor(s)

O`Malley, Ronald J.

Committee Member(s)

Bartlett, Laura
Wen, Haiming
Smith, Jeffrey D.
Wang, Tao

Department(s)

Materials Science and Engineering

Degree Name

Ph. D. in Materials Science and Engineering

Publisher

Missouri University of Science and Technology

Publication Date

Spring 2022

Pagination

xv, 106 pages

Note about bibliography

Includes_bibliographical_references_(pages 101-105)

Rights

© 2022 Yizhou Du, All Rights Reserved

Document Type

Dissertation - Open Access

File Type

text

Language

English

Thesis Number

T 12276

Download

Share

 
COinS