Effect of Fibre Size on Mechanical Properties and Surface Roughness of PLA Composites by Using Fused Deposition Modelling (FDM)

Abstract

Natural fibre as a reinforcing agent has been widely used in many industrial applications. Nevertheless, several factors need to be considered, such as the size and weight percentage of the fibre used in binding. Using fused deposition modelling (FDM), this factor was investigated by varying the size of natural fibre as the responding variable with a fixed weight percentage of kenaf fibre. The process of modifying the natural fibre in terms of size might increase the dispersion of kenaf fibre in the polymer matrix and increase the adhesion bonding between the fibre and matrix of composites, subsequently improving the interfacial bonding between these two phases. In this paper, the effect of fibre size was evaluated by performing the mechanical test, Scanning Electron Micrograph (SEM) to observe the morphology of the composites, and also by surface analysis. The surface roughness was visualised using a 3D profilometer and the figure was illustrated as colour shading in the image. The composite with fibre size ≤100 μm displayed better tensile and flexural strength, compared to other sizes. In conclusion, by reducing the size of the fibre, the composites could develop high strength performance for industrial applications.