Point defect behavior in pure V and V–A binary alloys, which contained undersized solute atoms, were examined by using high voltage electron microscope. In alloys, the number densities of self-interstitial atom loops were found to be much higher than that in

V, indicating that solute atoms trapped self-interstitial atoms and enhanced loop nucleation. Moreover, in contrast to the case of pure V, several stages were observed in the Arrhenius-type plot of the loop density. From the temperature dependence of the loop density in each alloy, the activation energies of 0.81, 0.65 and 0.99eV for V–xFe (x at least 0.1at%), V–yCr (y at least 1at%) and V–1Si were obtained, respectively. Complex loop shapes were observed in all of the alloys. Those became more significant with increasing solute concentration, thus indicating solute segregation to loops.

Effect of Undersized Solute Atoms on Point Defect Behavior in V–A (A = Fe, Cr and Si) Binary Alloys Studied by using HVEM. T.Hayashi, K.Fukumoto, H.Matsui: Journal of Nuclear Materials, 2002, 307-311[2], 930-4