Additive manufacturing of fused silica glass

Additive Manufacturing, of both metals and polymers, has seen rapid development in recent years, whereas the progress in glass has been rather slow. Today, glass can be considered the last frontier without a specialized 3D printing method available. Among different glass-like materials, silica glass is a high-performance material used in many parts of society. It is commonly associated with high mechanical, chemical, and thermal stability. The importance of 3D printing and additive manufacturing in the modern industry lies in the benefits and opportunities it facilitates. These include high flexibility in design and geometry, simplified production of customized objects, reduced material waste, and the ability to fabricate complex structures, often not possible when using traditional subtractive manufacturing.In this thesis, a novel method for additive manufacturing of silica glass is presented. Experiments and printed objects were madeusing the developed, experimental method. Here, by utilizinga method similar to the typical laser cladding, sintering of submicron silica powders was performed, and three-dimensional glass structures have been printed. Furthermore, by careful mixing of powders, a tailored composition of printed glass has been achieved. The high density and homogeneity of the printed parts made the developed method suitable for several different applications demonstrated in the last part of this thesis.The thesis describes the road from just an idea to the successful development of powder-based additive manufacturing of silica glass. The four papers in this compilation thesis show, first the setup development together with early-stage experiments (Paper I and II), and then there are two papers focused on early applications of the developed technology: one strictly mechanical (all-silica spotwelding, Paper III), and one optical (fiber prototyping, Paper IV).