Material extrusion-based-3D (MEX-3D) printing technology is popular for its simplicity and low cost; however, fabricated parts often exhibit high surface roughness. This study aims to minimize surface roughness in both longitudinal and transverse directions of MEX-3D printed poly (lactic acid) (PLA) parts using a slurry impact technique.
An L9 orthogonal array is constructed within a Taguchi framework coupled with weighted grey relational analysis (WGRA-Taguchi) to handle the multi-response nature of surface roughness data. PLA specimens are printed using a MEX-3D printer of three parameters at three levels, namely, build orientation at (0°, 45°, 90°) and layer thickness at (0.1, 0.2, 0.3 mm) before being subjected to slurry impacts at angles (15°, 45°, 90°). Analysis of variance (ANOVA) is performed on the weighted grey relational grades to evaluate and rank parameter significance.
The optimal parameter set for minimizing surface roughness is 0° build orientation, 0.1 mm layer thickness, and 90° slurry impact angle. ANOVA results reveal that layer thickness exerts the dominant influence on surface finish in both principal directions, followed by impact angle and build orientation.
To the best of the authors’ knowledge, this study is the first to implement the WGRA–Taguchi approach to achieve minimum surface roughness in MEX-3D printed parts by considering printing parameters alongside slurry impact parameters, aiming to achieve superior surface quality.
