Isothermal dendritic growth-A proposed microgravity experiment

Dendritic growth is one of the most common forms of crystallization in supercooled metals or alloys. The isothermal dendritic growth experiment (IDGE) is a microgravity flight-oriented scientific experiment aimed at testing and developing dendritic growth theory at small supercoolings. In the case of dendrites grown from pure, supercooled melts, growth is controlled by diffusion-limited transport of heat, which causes temperature gradients to be present in the liquid phase. Thermal gradients can excite anisotropic convection which affects the growth velocity, overall crystal morphology, and distribution of heat and solute. Dendritic growth, by its nature, does not permit independent manipulation of parameters which would rduce the vigor of melt convection under terrestrial conditions. The reduction of gravity through free fall is the only practical way to allow observation of 'convection free' growth and thereby provide a test of dendritic growth theory.