Adhesion of freshwater columnar ice to material surfaces by crystallization from the melt

Abstract

Abstract A new crystallization tower, based on the vertical draw, crystallization-from-the-melt technique of Czochralski, was designed, constructed, and validated for the growth of columnar ice on a range of material surfaces. In its current configuration, the crystallization tower can be used to grow crystalline laminates up to 75 mm thick on rectangular substrates that are up to 90 mm in diameter. Key to the success of this apparatus is the ability to independently control the temperature gradient between the substrate and liquid water reservoir as well as the speed of the linear stage used to regulate vertical motion. By imposing a slow draw rate with a small amount of undercooling, the ice laminates formed on the various surfaces showed close correspondence to the underlying rectangular shape of the substrates. With pre-seeding of the substrates, well-ordered polycrystalline ice with columnar microstructures was grown on aluminum and glass surfaces. Due to the rough, hydrophobic nature of Teflon, the microstructures were less ordered but still columnar. As a result of the low thermal conductivity of glass, larger undercooling was required to achieve growth on these surfaces as compared to aluminum. The crystallization tower can be used to grow ice directly on a variety of surfaces in a highly robust and automated fashion, which is of great utility to ice adhesion studies and investigations into the fundamental properties of ice.