Recovery studies of neutron-irradiated and deformed NiCr alloys

Abstract

Ni–10 wt% Cr and Ni–20 wt% Cr are irradiated with fast neutrons to fluences of 6.5 × 1021 and 1 × 1022 n/m2, and their isochronal annealing behaviour is studied between 343 and 945 K. On annealing, the resistivity increases between 343 and 575 K and decreases again at higher temperatures. The increase in resistivity is explained on the basis of an increase in local order on annealing. The decrease in resistivity at higher temperature arises because of dissociation of defect clusters.

COMPARISON STUDY BEWTWEEN THE RECOVERY BEHAVIOR OF DEFORMED QUENCHED, PRE-ANNEALED AND PULSED LASER DAMAGED Fe50Ni50 ALLOY BY MAGNETIC MEASUREMENTS

“…The isochronal annealing at stage I range from 125 to 500 ºC. Therefore the interstitial atoms migration could be definitely excluded in this temperature [25][26][27][28][29]. From this consideration, stage I could be attributed the structural change in the alloy matrix by short-range ordering promoted by migration of vacancies, formed by plastic deformation, quenching and laser damage Fe50Ni50 alloy to deep traps or sinks.…”

“…These processes cause microscopic homogeneities in the alloy matrix which lead to anomalous changes in the physical property measured. Moreover, the present binary alloy Fe50Ni50 of superstructure LI2 type (Ni3Fe) [10][11][12], its prospect as soft magnetic material and good corrosion resistance [13][14][15] at elevated temperature is of additional interest. This binary system forms a long range ordered intermetallic phase superstructure LI2 type (Ni3Fe) which has FCC unit cell with Fe atoms occupy the corners and Ni atoms occupy the middle of the faces of the cube [16] while in the disordered phase, Ni and Fe atoms randomly occupy the FCC lattice sites.…”