Jeong Beom Ko  Hyeon Beom Kim  Young Jin Yang

Vol. 30,  No. 3, pp. 211-219, Sep.  2024
10.7464/ksct.2024.30.3.211

Additive manufacturing 3D Printing Direct cure Direct printing Surface roughness Area error UV intensity Pattern spacing 보 문

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3D printing technology has created a paradigm shift in industries by achieving breakthrough innovations and enabling the fabrication of complex products. However, 3D printed parts are inferior in terms of their strength and surface quality compared to parts fabricated by conventional manufacturing methods. This study aims to improve the surface roughness of stereolithographic parts by experimental analysis of the generated area error. A photocurable polymer material was used for fabrication, and the effect of important parameters, such as the material viscosity, printing speed, pneumatic pressure, UV intensity, and pattern spacing, on the surface roughness were analyzed. The results showed that a high-viscosity (12,000 cP) thixotropic material formed a constant pattern with an aspect ratio of 1:1, and the pattern shape was maintained after printing. A pattern with a minimum thickness of 145 nm was formed at a printing speed of 70 mm/s and a pneumatic pressure of 20 kPa. These parameters were found to be suitable for low surface roughness. A UV laser at an intensity of 10 ~ 30 mW/cm2 was used to form a smooth surface at low curing intensities. Moreover, it was seen that with a pattern spacing of 110 ~ 130 nm, a stereolithographic part with a low surface roughness of Ra 1.29 nm could be fabricated.