Desenvolvimento de massa para impressão 3D por extrusão de geopolímero à base de vidro moído

Abstract

The search for new materials that can be used as more environmentally friendly alternatives to those currently in use is growing and has long been present in the industry. These studies have been further intensified with the popularity of additive manufacturing, which often relies on petroleum-derived raw materials, highlighting the need to investigate materials that are less harmful to the environment. Geopolymers are an example of materials that can offer a more environmentally friendly alternative with potential applications that are not currently met by conventional materials. The main objective of this study was to develop and analyze a material primarily composed of ground glass for 3D printing through extrusion. Initially, the amounts of Si, Al, and Na elements in the raw materials were determined using X-ray fluorescence analysis of the ground glass. The extruded mixture consisted of deionized water mixed with sodium hydroxide, and another part of the water was mixed with sodium silicate to disperse them. The dry mixtures of glass and aluminum oxide were then added to the two solutions. The alkaline solution/solid material ratio (AS/MS) ranged from 0.3 to 0.6. Starch was added to the mixture at concentrations ranging from 0 to 3%. The different compositions were tested for flexural strength using test specimens prepared in silicone molds. Overall, there was no significant variation in mechanical strength among the samples, except for the compositions with an AS/MS ratio of 0.5 without starch addition, where the composition with a 12M sodium hydroxide alkaline solution exhibited the highest mechanical strength. The printing test was conducted using a mass extrusion process on a 3D displacement table coupled with a testing machine. The best result was obtained with the mass left to rest for 7 days before the printing test to allow for a longer reaction time. From the extruded paths, it was observed that the studied masses had the ideal consistency for layer formation but lacked suitable properties for 3D printing with the tested compositions. Additionally, the vibration of the printing table contributed to layer fusion during the printing process.