▎ 摘　　要

Challenges in the development of carbon fibre and graphene reinforced composite polylactic acid material is reserved in this research. A screw extrusion process is used to blend the carbon fibre particle (1 wt.%) and graphene (1 wt.%) with poly lactic acid pellets (98 wt.%) to extrude and draw a continuous composite poly lactic acid wire. The size of the wire drawn is 1.75 mm and it is found uniform in shape. Through electron microscope, the dispersion of carbon fibre and graphene in the polylactic acid material is confirmed with good bonding. Subsequently, the presence of carbon fibre and graphene reinforcement in polylactic acid material is confirmed through the x-ray diffraction peaks. The composite polylactic acid material developed through screw extrusion is to build a mechanical test sample. The strength of composite polylactic acid material is 31 MPa and 3D printed composite polylactic acid material is 63 MPa. The density of the composite material is found increased in 3D printed material than the raw polylactic acid material. With valid mechanical and thermal properties of composite polylactic acid material, a commercial product is developed. An autoclavable COVID -19 face shield is designed and developed through Fused filament fabrication 3D printer and the same was implemented.