OPTIMIZATION OF PROCESS PARAMETERS AND MECHANICAL PERFORMANCE OF GRAPHITE-REINFORCED PHOTOPOLYMER COMPOSITES FABRICATED VIA STEREOLITHOGRAPHY (SLA)

Öz

With the increasing demand for functional and high-performance materials in the manufacturing sector, improving the mechanical properties of polymer composites produced using Stereolithography (SLA) has gained importance. In this study, the mechanical performance of composite samples produced by adding graphite at different ratios (0.3%, 0.5%, and 0.7%) to photopolymer resin was experimentally investigated. The graphite addition ratio, layer thickness (0.05–0.1 mm), and light exposure time (4–6 s) were selected as variable parameters during the production process, and the experimental design was analyzed using Response Surface Methodology (RSM). The findings showed that production parameters have different effects on tensile and flexural strengths. Increasing the graphite content decreased tensile strength by causing discontinuities in the matrix structure, while increasing matrix stiffness improved flexural strength. Furthermore, reducing layer thickness and increasing curing time increased polymerization efficiency, which positively affected mechanical performance in both test groups. Optimization revealed that the ideal parameters for tensile strength were 0.3% graphite content, 0.05 mm layer thickness, and 6 s curing time, while a higher graphite content (0.7%) was found to be more effective for flexural strength. This study demonstrates the critical importance of parameter optimization based on the intended use (tensile or flexural priority) in SLA-based composite production.

Anahtar Kelimeler

• Stereolithography (SLA)
• Photopolymer Composite
• Graphite
• Additive Manufacturing

Kaynakça

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