The crystallography and burgers vectors of dislocation loops in α-uranium

The orientation and Burgers vectors of the dislocation loops formed in α-uranium by neutron irradiation have been determined. The loops lie on (010) and (100) with Burgers vectors ½√(a 2+b 2)<110> and a [100] respectively. The loops are observed to lie in sheets, the loop planes co-planar with the sheet plane. The orientation of the two types of loops observed, and their Burgers vectors, are exactly as required to explain the irradiation growth phenomenon if the (010) loops are interstitial and the (100) loops vacancy. The arrangement of the loops in sheets, and the lack of mutual annihilation during annealing, can be explained in terms of the elastic interactions of the loops.