An apparatus for real time study of free dendritic growth: Design, manufacture and testing

Dendritic growth is a common mode of crystal growth observed in many metals, alloys and other materials. Recently, the use of electric current during solidification has been proposed as a suitable tool to modify the dendritic microstructures. Mechanisms by which an electric field could affect dendritic morphology are not entirely clear as it is difficult to study solidification phenomena during cooling. This research reports the design and manufacture of an instrument for in-situ study of dendrite growth of transparent model materials in the presence of an electric field. The system consists of an isothermal bath, a growth chamber and an optical and imaging system. The growth chamber is located inside the isothermal bath which controls the melting and subsequent cooling of the melt during solidification. The structure of the growth chamber is designed so that to allow for growth of only a single dendrite under the applied electric field. The solidification process of a transparent model material (succinonitrile) was observed using this instrument. During the experiments, photographs and videos of the single dendrite were obtained by an built-in optical and imaging system to explore the relationship between the electric current and the growth conditions.

Keywords:

Solidification , Free dendritic growth , Electric Current , Succinonitrile