Metal 3D printing with freeze casting

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The global needs of modern society demand durable materials that can be produced via sustainable technologies. In this project, we aim to build a state-of-the-art 3D metal printer, capable of not only building metal objects precisely but also with less energy consumption and without any GHG emissions. Upon success, this device will be coined as the most environment-friendly 3D metal printer - which will print metal objects of varied strength with different pore shapes and sizes. We propose to achieve this by integrating 3D printing (additive manufacturing) with the freeze casting process in the presence of a magnetic field.Lately, freeze casting has gained prominence as a viable environment-friendly approach to synthesize well-ordered porous materials. It involves the controlled freezing of a suspension (particles dispersed in a fluid) by inducing the temperature gradient in a particular direction. The growing ice lamella rejects the suspended particles from the moving front and accumulate them in the inter-crystal space. After solidification, the solvent is sublimated under reduced pressure, followed by subsequent posttreatment (sintering/densification). The directional freezing of the slurry thus serves the dual purpose of acting as a hard template and imposing self-assembly with spatially oriented macro-porosity and anisotropic properties. By combining freeze casting with additive manufacturing techniques, we can fabricate a whole new range of complex and irregular geometries.This approach will not involve any chemical reactions, thus avoiding any associated problems with the by-product removal, making it a safe, clean and green technology. The simplicity of the process, with easy template removal, allows us to employ a wide array of materials as "building blocks" apart from metals such as ceramics, polymers, carbon nanotubes, and biomacromolecules, which are otherwise unfeasible to use with the rest of the techniques. Evidently, the dream of sustainability lies in a green future and clean manufacturing techniques and 3D metal freeze printing surely do hold a key to it. In the cold climate of Alberta, where temperatures drop far below freezing point, a technique that employs freezing at its heart could thrive on rather easily in such conditions.