An updated facility for crystal growth with modeling of the conditions of crystallization in microgravity

The updated Zona-03 growth facility makes it possible to perform directiona l crystallization by the vertical Bridgman method modeling the crystallizat ion conditions typical of microgravity. Crystallization is conducted under the conditions of controlled axial heat flux with sample heating from above at controllable axial and radial temperature gradients and a preset level of axial and torsional vibrations supplied to the melt through the seed. An IBM PC controls the facility, measures the amplitude-frequency characteris tics of perturbations, and simultaneously performs the Fourier transform. E xperiments studying the effect of various perturbations on the development of convection in a melt and formation of microinhomogeneities in a crystal are carried out using this facility.