Tribological and hardness characteristics of resin materials in masked stereolithography: impact of washing solution and curing time

Abstract Masked stereolithography (MSLA) has emerged as a prominent vat photopolymerization technique due to its high-dimensional precision and superior surface finish, making it particularly suitable for applications in engineering, dentistry, and biomedicine. This study examines the influence of post-processing parameters; specifically washing solvent and UV curing time; on the mechanical and tribological behavior of three commercial resins: ABS-like (ABS), High Tough Resin (HTR), and Crown & Bridge resin (CrBr). Post-processing involved three solvents; 70% ethyl alcohol (E70), 95% ethyl alcohol (E95), and isopropanol (IPA); combined with three curing durations (3, 5, and 10 min). Mechanical performance was evaluated using Vickers hardness testing, while wear and frictional behavior were assessed through mass loss and friction coefficient measurements. The highest hardness (13.23 HV) was observed for CrBr following 10 min of curing and washing with E95. HTR demonstrated the best tribological performance, exhibiting the lowest mass loss (0.35%) and friction coefficient (0.188) under 10 min of curing and IPA washing. Analysis of variance indicated that resin type significantly influenced all measured properties ( p < 0.001), while curing time and solvent type had a statistically significant effect on hardness only. Taguchi signal-to-noise ratio analysis supported these findings and helped identify optimal post-processing settings. These results underscore the critical role of resin chemistry and post-curing conditions in tailoring the functional performance of MSLA-fabricated components.