Ordered distribution of bubble complexes induced by the planar defects

Abstract

The interaction between He bubbles and planar defects can lead to an ordered distribution of bubbles that serve as a strong inhibitor of dislocations. Systematic research into this phenomenon is therefore essential to reduce irradiation hardening. However, the mechanisms behind the formation of this phenomenon are still unclear. In this work, using the in-situ 20 keV He⁺ irradiation method, bubble arrays in SiC were formed by the two-dimensional confinement effect of the planar defects. The subsequent irradiation process led to size growth and overlapping of the bubbles, resulting in a coral-like bubble structure that could be observed the [011] zone axis. For the first time, the observation of bubble bridges forming between the primary faulted planes with a larger average bubble size was reported. They formed by the preferential accumulation of vacancies at the junction of planar defects or the incoherent twin boundaries.