Incorporation of Gold Nanoparticles for Enhanced Additive Manufacturing and 3D Printing Applications of Novel ‘Smart’ Materials

Abstract

Advanced additive manufacturing (AM) and 3D printing technologies and techniques have the capacity to revolutionize the way composite materials are produced, manufactured, utilized and repaired across a growing number of fields and applications. This research focuses on the design and development of a new category of ‘nanofunctionalized’ 3D printed parts and materials. On the length scale of several micrometers to nanometers, nanomaterials tend to exhibit unique material properties not often seen in the bulk state that can be utilized for a variety of sensing and material state monitoring applications. During initial testing, we have successfully demonstrated the ability to modify precursor filament to obtain nano-functionalized 3D printed parts and materials. By combining the unique optical properties of gold nanoparticles within a polylactic acid polymer host matrix, we herein present an alternative approach for defect detection in 3D printed parts and materials. Changes in absorbance intensity for 3D printed parts containing gold nanoparticles is studied to determine a relationship between void space, representative of material defects or missing print layers, and absorbance intensity. It is shown that as few as 2 missing print layers (0.2 mm thick void) can be detected within a 0.1% difference when compared control samples using the optical response of gold nanoparticles alone. This work aims to use this type of relationship to quantify and assess the structural integrity of 3D parts and materials prior to and throughout their use. This paper demonstrates that by utilizing a ‘bottom-up’ approach to the AM process, with an initial focus on the selection and design of precursor materials to enable 3D printed parts, in-situ material state monitoring for defect detection can be enabled.