Formation of substitutional-interstitial clusters in dilute alloys: Development of previous models

The anelastic behaviour of crystalline solids containing light interstitials and trapping substitutional impurities has been theoretically investigated. New formulas have been derived which allow the calculation of the concentration of substitutional-interstitial (SI) clusters as a function of the overall contents of substitutional and interstitial impurities. The formation of higher order complexes such as SI, is also considered. The effect of short-range repulsive interactions among the interstitials is taken into account in the framework of the hard-sphere model.