Mechanical and physical characterization of SLA 3D-Printed water-washable composites for high-precision jewelry applications

This study investigates the mechanical and physical properties of SLA 3D-printed water-washable resin (WWR) composites reinforced with Kevlar powder (KP), aiming to optimize their performance for high-precision jewelry applications. Four composite formulations with varying KP concentrations were fabricated and systematically characterized through tensile, toughness, hardness, surface roughness and water absorption tests, complemented by scanning electron microscopy (SEM) analysis. Statistical analysis (n = 3, with standard deviations and error bars) was applied to ensure data reliability. Results demonstrated significant improvements in mechanical performance: tensile strength increased by up to 43.87 %, hardness by 18.1 % and modulus of elasticity by 24.84 %. Toughness improved by 45.72 % between S1 and S2, though elongation decreased by 5.77 %, indicating reduced flexibility at higher KP content. Surface roughness (Ra) increased initially by 86.12 % but stabilized beyond S3, while water absorption decreased by 8.08 % in S4, reflecting improved filler–matrix integration. SEM analysis confirmed a transition from brittle fractures in neat resin to a more uniform reinforcement distribution at optimal KP loading. These findings demonstrate that KP-reinforced WWR composites offer enhanced durability, wear resistance and precision for jewelry applications, while careful post-processing is recommended to balance surface quality and mechanical performance.