The influence of acceleration forces on nucleation, solidification, and deformation processes in tin single crystals

Abstract

Growth orientations are given for 50 gram and 2 gram single crystals of tin grown at acceleration levels of 1 through 7-g. Acceleration gradients produce a preferred growth orientation effect not previously observed for tin. Convection currents at approximately 5-g encourage multiple nucleation and subsequent random orientation of growth direction. The macromosaic substructure in the 99.95 pct tin does not obey the(RG) ^-1 growth relationship. The shape of the growth interface changes smoothly as the acceleration force increases, with the direction and magnitude of the change dependent on growth orientation. Deformation effects such as recrystallization and twinning are observed at acceleration levels greater than 2-g. A {431} twin plane was obtained for crystals grown at 6-g’s.