EXPERIMENTAL INVESTIGATION OF TENSILE AND IMPACT BEHAVIOR OF SLA-PRINTED PHOTOPOLYMER COMPOSITES REINFORCED WITH MILLED CARBON FIBER

Abstract

Additive manufacturing technologies enable the production of complex geometries with low material waste and manufacturing cost. Among these technologies, stereolithography (SLA) has attracted considerable attention due to its high printing resolution and surface quality. However, the mechanical performance of photopolymer parts produced by SLA is often limited for structural applications. In this study, the tensile and Charpy impact behavior of SLA-printed photopolymer composites reinforced with milled carbon fiber particles was experimentally investigated. Specimens were produced at five different infill ratios (20%, 40%, 60%, 80%, and 100%) and five different reinforcement contents (0, 0.4, 0.8, 1.2, and 1.6 wt.%). Tensile tests were conducted according to ASTM D638 Type V standard, while Charpy impact tests followed ASTM D256. The results showed that increasing the infill ratio significantly improved both tensile strength and impact toughness, while the addition of milled carbon fiber particles generally reduced the mechanical performance of the printed composites. The highest mechanical properties were obtained in specimens produced with 100% infill and without reinforcement. These findings provide new insight into the combined effects of infill ratio and particle reinforcement and may serve as a practical guideline for improving the mechanical performance of SLA-printed photopolymer composites.