Accession Number : ADA194229

Title :   Detection of Irradiation Effects on Reactor Vessel Steels by Magneto-Acoustic Emission.

Descriptive Note : Technical rept. 1987-1988,

Corporate Author : CALIFORNIA UNIV LOS ANGELES DEPT OF MATERIALS SCIENCE AND ENGINEERING

Personal Author(s) : Kwon, Oh-Yang ; Ono, Kanji ; Lucas, Glenn E ; Oddette, G R

PDF Url : ADA194229

Report Date : 21 Apr 1988

Pagination or Media Count : 9

Abstract : The irradiation effects of reactor vessel steels were studied by magneto-acoustic emission (MAE). MAE is a new method of non-destructive evaluation. It is generated primarily by domain wall motions during magnetization of ferromagnetic materials in the alternating magnetic field. Since MAE activity is sensitive to the microstructural changes, it is applied to determine the status of steel samples exposed to neutron irradiation. Two commercial steels, A302B plate and A533B weld, and two model alloys were irradiated at four different conditions; high and low flux, two fluence levels and three temperatures. For each material/condition and unirradiated control samples, MAE intensity in rms voltage with increasing magnetic field was measured. Direct and envelope-detected MAE waveforms were also recorded. Measurements were also made for the samples unirradiated but aged at 288 C up to 278 hours in order to separate the effects of thermal aging from irradiation effects. Barkhausen effects were also investigated using a surface probe. The results presented here show that MAE waveform analysis can be a promising non-destructive evaluation technique for monitoring the microscopic changes in the steel components subjected to neutron irradiation.

Descriptors :   *NEUTRON IRRADIATION, *NONDESTRUCTIVE TESTING, *RADIATION DAMAGE, *REACTOR MATERIALS, AGING(MATERIALS), ALLOYS, DETECTION, DOMAIN WALLS, FERROMAGNETIC MATERIALS, FLUX(RATE), IRRADIATION, MAGNETIC FIELDS, MAGNETIZATION, MAGNETOACOUSTICS, MATERIALS, MICROSCOPY, MICROSTRUCTURE, MODELS, MODIFICATION, MOTION, PROBES, SAMPLING, STEEL, SURFACES, TEMPERATURE, THERMAL PROPERTIES, WAVEFORMS, ACOUSTIC EMISSIONS

Subject Categories : Fission Reactor Materials
      Radioactiv, Radioactive Wastes & Fission Prod
      Test Facilities, Equipment and Methods

Distribution Statement : APPROVED FOR PUBLIC RELEASE