Microstructural characteristics and mechanical properties of 3D printed Kevlar fibre reinforced Onyx composite

The main objective of this study is to develop the Kevlar fibre reinforced Onyx composite (KFRO) material by employing the 3D printing technology and examine the effect of Kevlar fibre reinforcement percentage on microstructural characteristics and mechanical properties of developed composite material. The methodology of continuous fibre reinforced composites (CFRC) was followed and the Kevlar fibre reinforcement % was varied as 10 %, 20 % and 30 % in the composite material fabrication. Results disclosed that the KFRO composite 3D printed using 30 % Kevlar fibre reinforcement in Onyx matrix yielded greater tensile strength of 124 MPa, flexural strength of 105 MPa, impact toughness of 2.4 J and shore hardness of 76 D. The mechanical properties of KFRO composite were significantly improved at 20 % of Kevlar fibre reinforcement compared to 10 % of Kevlar fibre reinforcement. Further increase in Kevlar fibre reinforcement up to 30 % showed slight enhancement in mechanical properties of KFRO composite when compared to 20 % of Kevlar fibre reinforcement. The overall strength improvement is a result of the increased reinforcement, precise alignment of fibres in the loading direction, and the uniform distribution of fibres within the onyx.