Fractal characterization of conductive Ag/flexible 3D printed PLA

Abstract

In this paper, thin and flexible PLA plates were prepared through FDM printing process. The traditional FDM process was adopted at predetermined optimal printing parameters of the 3D printer. The CAD designs of the samples were built on SpaceClaim modeler (ANSYS® 2019). The slicing and generation of the toolpath (gcodes) were undertaken in Cura software whereas the printing undertaken using a Desktop 3D printer (WANHAO Duplicator D10). The flexible PLA samples were designed for conductivity in smart devices; as such, they were coated with microfilms of highly conductive silver paint through a dipping method. The dipping was carefully undertaken in which the samples could soak inside the paint for 40 seconds and then removed and allowed to dry in vacuum desiccators for 12 hours. The samples were then heat treated at varying times (0, 10 and 20 minutes) in an oven at a constant temperature of 100°. The samples were then profiled using atomic force microscopy to obtain the microroughness characteristics of the Ag/PLA surfaces. The height features as well as spatial roughness characteristics were obtained through mono-fractal and multifractal approaches. The influence of heat treatment times at the reported temperature is shown to significantly shown to influence the spatial roughness characteristics of the 3D printed flexible samples.