Multimodal Freezing System for Cryogenic 3D Printing

Abstract Cryogenic 3D Printing (Cryo-3DP) creates 3D objects by deposition-then-freezing of aqueous solutions of various materials layer-by-layer. The process generally takes place at the temperature ranging from -20 °C to -25°C. At the beginning of the process, cryo-3DP demands a high cooling rate to reduce the work envelope’s temperature rapidly. After the work envelope reaches the working temperature (-20 to -25°C), lower cooling rates are enough. The proposed multimodal freezing system uses two modes of cooling. Rapid injection of the CO2 gas in the chamber is suitable for achieving high cooling rates (0.5 °Cs-1) initially and Vapor Compression Refrigeration (VCR) for sustained heat removal from the system (0.5 °Cmin-1). The results show that the proposed multimodal system performs faster than the conventional system.