Additive manufacturing of polyethylene terephthalate glycol /carbon fiber composites: An experimental study from filament to printed parts

Abstract

This research focuses on the definition and application of a characterization methodology to determine the characteristics of fused deposition modeling 3D printing materials. Commercial short fiber reinforced and unreinforced polyethylene terephthalate glycol parts were tested achieving comparison terms. The presented methodology is composed of three classes: thermal analysis, mechanical testing, and material morphology. Filament was tensile tested with specially developed setup for determining the mechanical properties of raw materials. Standardized flexural and tensile samples were printed 100% dense in both materials and tested. Differential scanning calorimetry results showed that the thermal properties of both materials do not change with successive heating cycles. Thermogravimetric analysis allowed to understand the thermal stability of materials and quantify the amount of fiber in the matrix. Tensile tests indicated that the addition of fibers increases the Young’s modulus by 70.10% but there is lesser withstanding of stress by 28.21%. Flexural tests exhibited an increase in flexural modulus of 191.38% and 5.14% in flexural strength for the reinforced polyethylene terephthalate glycol, due to the presence of fiber. Microscopic analysis revealed a 12% of void spots and fiber alignment accordingly to the deposition path.