Thermal and mechanical behavior of biocomposites using additive manufacturing

Research on additive manufacturing (AM) has gained significant attention in recent years. In this study, two different matrices of polypropylene and polylactic acid materials filled with three different percentages of wood flour were employed; namely 10, 20, and 30%. Biocomposite filaments (developed by twin screw extrusion) were further used in AM by fused deposition modeling (FDM) to obtain testing samples for the characterization of the tensile and flexural properties through mechanical testing. Tensile and flexural mechanical properties of the composite material obtained by AM-FDM were compared against those obtained by injection molding. Experimental results showed that samples obtained with a percentage of 20% of wood flour showed lower mechanical properties, while those obtained at 30% testing samples turned very brittle. Mechanical properties like flexural stiffness were higher in the testing samples obtained by injection molding compared to those by AM-FDM. To understand the thermal behavior of the composites, specimens were subjected to TGA experimentation. Experimental results show an analysis of the optimum temperatures for processing the composites through AM, and provide evidence that these composites could potentially be applied in the design of auto parts due to their biodegradability and mechanical strength.