Assessment of creep damage of ferromagnetic material using magnetic inspection

Author

Chen, Z.J. ; Govindaraju, M.R. ; Jiles, D.C. ; Biner, S.B. ; Sablik, M.J.

Author_Institution

Ames Lab., Iowa State Univ., Ames, IA, USA

Volume

30

Issue

6

fYear

1994

fDate

11/1/1994 12:00:00 AM

Firstpage

4596

Lastpage

4598

Abstract

Results of inspection creep damage by magnetic hysteresis measurements on Cr-Mo steel are presented. It is shown that structure sensitive parameters such as coercivity, remanence and hysteresis loss are sensitive to the creep damage. Previous metallographic studies have shown that creep changes the microstructure of the material by introducing voids, dislocations, and grain boundary cavities. As cavities develop, dislocations and voids move out to the grain boundaries; therefore the total pinning sources for domain wall motion are reduced. This, together with the introduction of demagnetization field due to the cavities, results in the decrease of both coercivity and remanence. Numerical computations with a modified Jiles-Atherton model are presented which are consistent with the proposed mechanisms

Keywords

alloy steel; coercive force; creep; crystal microstructure; demagnetisation; dislocations; ferromagnetic materials; grain boundaries; magnetic domains; magnetic hysteresis; remanence; voids (solid); Cr-Mo steel; Jiles-Atherton model; coercivity; creep damage; demagnetization; dislocations; domain wall motion; ferromagnetic material; grain boundary cavities; hysteresis loss; magnetic hysteresis; magnetic inspection; microstructure; remanence; structure sensitive parameters; voids; Coercive force; Creep; Grain boundaries; Inorganic materials; Inspection; Magnetic hysteresis; Magnetic materials; Microstructure; Remanence; Steel;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.334160

Filename

334160