Magnetic analysis of nuclear pressure vessel steels and other ferromagnetic materials subject to neutron irradiation and heat treatment

Mechanical and magnetic property changes due to neutron irradiation and heat treatment were investigated for the sake of developing a nondestructive method of monitoring nuclear pressure vessel steel embrittlement during reactor operation. Four kinds of samples, including pressure vessel steel, pure Fe and Ni, Fe-Cu alloys and Charpy surveillance coupons, were examined. An automated magnetic property measuring system was constructed and measuring schemes were established. Microhardness and magnetic coercivity, remanence, permeability, and hysteresis loss were measured as a function of a variety of irradiation and annealing exposures. The results were interpreted in terms of dislocation and magnetic domain wall pinning mechanisms and internal stress relaxation. It is found that the pinning mechanisms of dislocations and domain walls are different with respect to the effective pinning parameters. However, stress relaxation has similar effects on both microhardness and magnetic coercivity. It is concluded that the selection of testing material, specimen size and shape, and magnetizing scheme are important factors for constructing a nondestructive testing method for reactor pressure vessel surveillance.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Nuclear, Plasma, and Radiological Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Shong, Wei-Ja

Contributors dc:contributor

• Stubbins, James F.

• Engineering, Nuclear
• Engineering, Metallurgy
• Engineering, Materials Science

Statement dc:rights

• Copyright 1995 Shong, Wei-Ja

Language dc:language

eng

Identifier

AAI9624498
(UMI)AAI9624498

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/22654