Direct Ink Writing Glass: A Preliminary Step for Optical Application.

Bo Nan,Ryszard Buczyński,Przemysław Gołębiewski,Francisco J Galindo-Rosales,José M F Ferreira

doi:10.3390/ma13071636

Abstract

In this paper, we present a preliminary study and conceptual idea concerning 3D printing water-sensitive glass, using a borosilicate glass with high alkali and alkaline oxide contents as an example in direct ink writing. The investigated material was prepared in the form of a glass frit, which was further ground in order to obtain a fine powder of desired particle size distribution. In a following step, inks were prepared by mixing the fine glass powder with Pluoronic F-127 hydrogel. The acquired pastes were rheologically characterized and printed using a Robocasting device. Differential scanning calorimetry (DSC) experiments were performed for base materials and the obtained green bodies. After sintering, scanning electron microscope (SEM) and X-ray diffraction (XRD) analyses were carried out in order to examine microstructure and the eventual presence of crystalline phase inclusions. The results confirmed that the as obtained inks exhibit stable rheological properties despite the propensity of glass to undergo hydrolysis and could be adjusted to desirable values for 3D printing. No additional phase was observed, supporting the suitability of the designed technology for the production of water sensitive glass inks. SEM micrographs of the sintered samples revealed the presence of closed porosity, which may be the main reason of light scattering.

Highlights

After almost thirty years of development, additive manufacturing, or commonly named 3D printing, has started to play an important role in the modern industry such as automobile, aerospace, bioengineering, and so on, and the interest of research still maintains enthusiasm [1,2,3,4,5]
It can be difficult to apply shaping techniques for glasses that are based on powder densification, as the main issue is its behavior in elevated temperatures
Unlike sintering ceramics or metals, a glass starts to flow as a viscous material after reaching the transition temperature

Summary

Introduction

After almost thirty years of development, additive manufacturing, or commonly named 3D printing, has started to play an important role in the modern industry such as automobile, aerospace, bioengineering, and so on, and the interest of research still maintains enthusiasm [1,2,3,4,5] It is a near-net shaping, and a moldless shaping method, that can be readily categorized into two different types, namely light-based and ink-based 3D printing [6], or into seven different types, according to the classification of American Society for Testing and Materials (ASTM) 52900:2015 standard [1]. Research on liquid processing glass, especially connected with additive manufacturing, focuses mainly on silica-rich [12,13] and bioactive glasses [14,15], as the first type is more resistant to thermal shock and allows the production of dense and transparent samples, and the latter type is preferred in porous scaffold formed to enhance its bioactivity and osteointegration potential

Methods

Results

Conclusion