Establishing a Correlation Between Mechanical Properties and 3D Printing Process Parameters for Chopped Carbon Fibre Reinforced Nylon Composite

The usage of additive manufacturing (AM) as a production technology for end-use products has increased due to advancements in the field. It permits the production of more complex parts with least waste material at a relatively low cost. Recent advancement in the domain is additive manufacturing of fibre reinforced polymer (FRP) materials having high strength to weight ratio. However, the mechanical properties of additively manufactured components depend upon the process parameters. This paper presents the correlation study of Fused Deposition Modelling (FDM) process parameters with mechanical properties of additively manufactured Nylon-Carbon fibre composite material. Infill density, layer thickness and infill orientation were the process parameters considered based on their influence on the strength of the component. Tensile strength, compressive strength and impact strength were considered as the response parameters. Tensile specimens were fabricated as per ASTM D638- Type I standard, while compressive and impact test specimen were fabricated as per ASTM D695 and ASTM D256 standards respectively. A fractional factorial Taguchi orthogonal array- L9 (3 parameters, 3 levels) was developed, and the influence of the process parameters was evaluated using Taguchi analysis. Based on the parametric study, the result showed that the infill density prominently influenced the strength of the component. Inverse proportionality was observed between the layer thickness and tensile & compressive strength, whereas impact strength exhibited direct proportionality with the layer thickness. Furthermore, tensile and compressive strength increased when the infill orientation was aligned with the loading direction, while impact strength increased with cross-oriented infill.