In the present work, the pair interaction of coaxial circular prismatic dislocation loops (PDLs) arbitrary placed in elastic solids with free spherical surfaces is considered. The analytical solutions for the pair interaction energies of PDLs in an elastic sphere, an elastic medium with a spherical pore and a spherical layer are given in the form of double power series and illustrated by energy maps built in the space of the normalized PDL radii and axial...

Self-organization mechanisms promoting elimination of cracks in thick GaN layers grown on sapphire substrates are considered on the basis of the experimental results on the fabrication of the layers by Hydride Vapor-Phase Epitaxy on MOCVD-grown GaN/Al2O3 templates. The obtained data support the supposition on the closure of tensile stress-related cracks via diffusion processes and demonstrate the strong contribution of bulk diffusion in addition to surface diffusion discussed earlier.

In the present work, using the method of a composite piezoelectric oscillator at a frequency of 99-102 kHz, polycrystalline magnesium was studied under two types of treatment: deformation and subsequent annealing. The influence of these types of treatments on changes in the dislocation density and such an important structurally sensitive parameter as the dynamic Young's modulus has been established. The values of micro-yield stress are determined. With a longitudinal deformation of 1.7%, at the strain...