Internal friction and magnetic properties of thermally aged Fe–1 wt.% Cu alloys

Abstract

Abstract-The purpose of this study is to investigate the internal friction (IF) behaviour of thermally aged Fe-Cu alloys that are model specimens simulating for the irradiation embrittlement of nuclear reactor pressure vessel (RPV) steels. Plate-shaped specimens of Fe-1wt.%Cu alloy were quenched from 1123 K and thermally aged at 773 K for 10 3 min. The IF of the specimens was measured without magnetic field using the free resonant bending vibration method. Magnetic hysteresis loops and conductivity was also measured. The IF value, hysteresis loss, and conductivity increased under thermal aging, which suggests that the IF characteristics are closely related to the change of electromagnetic eddy-current loss due to the depletion of Cu solute atoms. This study demonstrates the possibility of the application of IF measurement as one of the tools for nondestructive characterization of degradation processes of irradiated RPV steels.

Internal Friction and Magnetic After-Effect Study of Dislocation Dynamics in Thermally Aged Fe-1%Cu-C Alloys

“…The various stages of copper precipitation are achieved by a thermal aging of samples (dimensions: 1.3 × 1.3 × 30 mm 3 ) at 773 K (500 °C) in an argon atmosphere, and subsequent fast quenching into the water. The duration of heat treatments varied from 0.1 to 480 h. This temperature is chosen to achieve the peak hardening in a reasonable time (15 h) [11], while different aging times are chosen to create different hardening stages.…”

Magnetic after-effect study of dislocation relaxation in Fe-based alloys

“…The various stages of copper precipitation are achieved by a thermal aging process of Fe-1%Cu samples, consisting of time-dependent heat treatments at 773 K (500 o C) in argon atmosphere, and subsequent fast quenching into water. The duration of heat treatments varied from 0.1 h to 480 h. This aging temperature is chosen in order to achieve the peak hardening in a reasonable time (15 h) [26], while different aging times are chosen in order to create different hardening stages.…”