Comparison of mechanical properties of different 3D printing technologies
Awutsadaporn Katheng, Wisarut Prawatvatchara, Patcharanun Chaiamornsup, Tanapon Sornsuwan, Hathairat Lekatana, Jadesada Palasuk
Abstract
This study evaluated and compared the mechanical properties of provisional 3D-printed polymers fabricated using three commonly used 3D printing technologies: stereolithography (SLA), digital light processing (DLP), and liquid crystal display (LCD). Ninety specimens, both bar-shaped and disc-shaped, were printed using standardized resin color and print settings for each technology. Flexural strength was measured using a universal testing machine, while surface hardness and roughness were evaluated using a micro-Vickers hardness tester and atomic force microscopy, respectively. Statistical analyses were performed using one-way ANOVA and Tukey’s post-hoc tests at a significance level of p < 0.05. SLA demonstrated the highest flexural strength (93.39 ± 5.57 MPa), significantly higher than DLP (69.97 ± 8.48 MPa) and LCD (64.69 ± 8.98 MPa). Surface hardness was comparable across SLA (18.80 ± 0.57 kgf/mm 2 ), DLP (17.80 ± 1.85 kgf/mm 2 ), and LCD (18.27 ± 0.93 kgf/mm 2 ). In terms of surface roughness, SLA showed the lowest mean value (14.79 ± 7.96 nm), followed by DLP (24.59 ± 9.76 nm), and LCD exhibited the highest roughness (89.87 ± 28.26 nm). The findings indicate that SLA produces polymers with superior flexural strength and the smoothest surface finish, making it preferable for applications requiring strong, high-quality surfaces, while DLP and LCD provide alternative benefits in specific use cases.