Collision cascades in iron and niobium

Defect production by collision cascades in fcc iron and niobium was studied using a computer experiment approach. Cascades with energies up to 975 keV and 594 keV were studied for iron and niobium, respectively. In the case of iron, the primary defect state produced directly by each cascade was subjected to short-term annealing (STA) simulation at 5660C. Recipes for the numbers of free defects, defect clusters, microvoids and interstitial loops after STA, as functions of cascade energy, were constructed from the annealing computer experiment results. In the case of niobium, the primary defect state is described. For a given PKA energy, the displacement production in niobium was about 18 percent smaller than that in iron. The cascade size in niobium was about the same as that in iron up to 100 keV