Volumetric additive manufacturing of mullite from colloids

Ceramic materials possess many desirable properties, such as mechanical strength, thermal stability, hardness, chemical resistance and electrical, optical, and magnetic properties of high technological relevance. The most challenging tasks of modern engineering are the design and the development of advanced ceramics for next-generation applications, ranging from automotive to aerospace, energy, environmental, and biomedical sectors. The wide industrial use of advanced ceramic materials depends on the technological possibility to fabricate near-net-shaped or ideally net-shaped 3D ceramic-based parts with the required geometry and functionality. Since the post-machining of ceramics is a time-consuming and expensive process that can make up for 80% of the overall manufacturing costs of a ceramic product, nowadays Additive (or generative) manufacturing (AM) is receiving great interest. AM is defined as “the process of joining materials to make objects from 3D model data, usually layer upon layer, as opposed to subtractive (and formative) manufacturing methodologies, such as traditional machining”. So, with AM, three-dimensional objects are assembled by point, line or planar addition of material without the need of tooling and this opens up completely new fields of research and applications, but also requires changes in the way of thinking at the design. In this field, one of the last developments is the tomographic volumetric additive manufacture , that allows to print an entire three-dimensional object by irradiating a liquid photopolymer volume from multiple angles with dynamic light patterns. In this work, with the use of this new technique, the main purpose is to obtain a pure monophasic solid of mullite with a specific simple 3D shape. The biggest focus is set on the composition, then with the use some addictions, a compromise for a good shape is searched.