Melting and misalignment of solid crystalline krypton inclusions in aluminium

Ion implantation induced crystalline krypton inclusions in aluminium, epitaxially aligned with the matrix, have been investigated with X-ray diffraction and Rutherford backscattering, channeling analysis. The data show a dual size distribution of the krypton bubbles. In samples annealed up to 620 K and subsequently cooled, the larger bubbles melt in a pressure broadened transition at 114-118 K. The smaller bubbles remain solid upon heating but, as a result of a roughening transition on the aluminium facets of the cavities, the Kr crystallites gradually loose their epitaxial alignment. (orig.)