Absence of random voids in the spatially ordered void ensemble

Abstract

The void evolution in the presence of one-dimensionally (1-D) migrating self-interstitials is considered. No saturation of the void swelling due to 1-D self-interstitials is assumed. Void growth rate is considered to be driven by the dislocation bias, and undergoes the stochastic fluctuations caused by the random nature of point defect jumps and collision cascade initiation. Void nucleation and subsequent growth are investigated. It is shown that initially nucleated random voids start shrinking already when the spatially aligned voids make a small fraction of the void ensemble. Despite a continuous generation of small void embryos in the random spatial positions and negligible vacancy emission, development of the random void population becomes completely suppressed by the stochastic fluctuations when the aligned voids are the major sinks for point defects and the fraction of 1-D self-interstitials is small but not negligible.