Effect of inorganic chalk additive on 3D-printed polylactic acid specimens

Abstract This work examines the influence of an inorganic chalk-based additive on the quality and mechanical properties of products produced by 3D printing using the fused filament fabrication (FFF) method from polylactic acid (PLA). The use of inorganic additives is common mainly to reduce material costs and modify mechanical properties. Regarding the potential for material savings, the effects of different infill patterns (strain and octagonal) and densities (0, 50, and 100 %) were also tested in the study. The test specimens were evaluated using mechanical tests, qualitative surface morphology analysis with a digital optical microscope featuring a large depth of field, and thermal analysis. The work also included a finite element method (FEM) simulation to analyse the mechanical behaviour of the specimens under study. The FFF process is influenced by several parameters, such as printing temperature, substrate temperature, printing speed, and printing orientation, which have a fundamental impact on the resulting product quality. The results show that the amount and choice of additive significantly affect the mechanical properties and overall quality of printed parts, which emphasises the need to optimise both material composition and printing parameters.