Tensile and Fatigue Analysis of Functionally Graded Materials produced by Fused Filament Fabrication

Abstract

The aim of this research study is the design, fabrication, and mechanical characterization of functionally graded composite materials using the fused filament fabrication (FFF) process. Chopped carbon fibre reinforced Polyethylene Terephthalate Glycol (CCF-PETG) and CCF-Nylon materials are fabricated by the Zmorph Fab desktop machine. The digital design of gradient structures is achieved by the voxelization process of the computer aided design (CAD) files. One of the main drawbacks of FFF parts is weak in shear strength that is due to the orientation of the raster plane, so FGM is one of the ways to enhance the mechanical properties of the material. Tensile behaviour of FGM parts fabricated in various processing parameters such as print directions, infill orientations, layer heights, etc. Tensile fatigue tests with a stress ratio of 0.1 were performed on each specimen at 90, 80, 70, and 60% of UTS. This knowledge-based study will be conducted with the hypothesis that the tensile strength of CF PETG and CF Nylon materials are less than that of functionally graded CF PETG and CF Nylon materials. The specimen's longest fatigue life was found at a stress level of 60%. This study presents a first-of-its-kind experimental examination of FGM tensile and fatigue characteristics.