title: Viscous fingering and dendritic growth of surface crystallized Sr2TiSi2O8 fresnoite.
abstract: During the quenching of a melt with the composition 2SrO·TiO2·2.75SiO2, cubic SrTiO3- and tetragonal Sr2TiSi2O8-crystals are formed at the surface. Subsequent crystal growth leads to dendritic fresnoite structures which become increasingly finer until the mechanism changes to viscous fingering during further cooling. In the final stages of this initial growth step, the crystal orientations of these dendrites systematically change. Due to a complete absence of bulk nucleation in this system, crystal growth is resumed upon reheating to 970°C and fractal growth with the c-axis tilted by about 45° from the main growth direction is observed. The results are interpreted to confirm the link between viscous fingering and dendritic growth in the case of a true crystallization process.
authors.affiliation: Otto-Schott-Institut, Jena University, Fraunhoferstr. 6, 07743 Jena, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wisniewski
authors.affiliation: Otto-Schott-Institut, Jena University, Fraunhoferstr. 6, 07743 Jena, Germany.
authors.forename: Marek
authors.initials: M
authors.lastname: Patschger
authors.affiliation: Otto-Schott-Institut, Jena University, Fraunhoferstr. 6, 07743 Jena, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Rüssel