PRINTING PARAMETER IMPACT ON PLA MATERIAL FRACTURE TOUGHNESS RESULTS

Abstract

The structural life of a functional component includes the period when the component has developed some sort of defect (e.g., crack). In such cases, damage-tolerant design utilizes fracture mechanics parameters for the assessment of the component’s structural capability to withstand loads expected in the exploitation. One of the most fundamental parameters is the stress intensity factor, which characterizes the stress state near the crack tip. The critical value of this parameter is called fracture toughness, and it is the most suitable failure criterion for brittle materials. One of the most used materials in fused deposition modeling (FDM) technology is PLA polymer, known for its brittle behaviour. Due to good mechanical properties in comparison with other FDM polymers and excellent biocompatibility, the PLA material is not just a material for prototyping purposes but may also serve as a material for functional applications in medicine, food packaging, etc. The FDM printing parameters influence the final component's mechanical properties. The aim of this paper is to assess the impact of printing parameters, such as layer height, infill density, and raster orientation, on fracture toughness values.