The Effect of Solute Concentration on the Formation of Loops in Aluminium‐Magnesium Alloys during Fission Fragment Irradiation

Abstract

AbstractA study has been made of the effect of magnesium concentration (up to 0.5 at%) on the formation of dislocation loops in aluminium during fission fragment bombardment at 60 °C. Increasing magnesium content reduces the initial rate of increase of the total loop area with dose, but the loop area saturates at a higher level in more concentrated alloys. A concentration as low as 0.02% reduces the initial rate of loop growth by a factor of 4 to 5. Considerable attention has been given to the problems of obtaining accurate measurements of the loop area per unit volume in foils irradiated in the pre‐thinned state, and a number of corrections have been applied. An unusual surface denudation effect is observed. The results are explained in terms of the effect of trapping on the mobility of both the interstitial atoms and the vacancies.