Accuracy evaluation of thin wall features fabricated by fused deposition modeling using reinforced composite materials

Abstract

Additive manufacturing (AM) using the standard polymer in material extrusion technique often leads to defects such as warping effects, shrinkage and low dimensional accuracy, which will decrease its functionality. Hence, composite materials were introduced to cater the above-mentioned problems. Unfortunately, the FDM composite-related research primarily focuses only on the improvement of mechanical properties where its manufacturability to produce different types of geometries is currently limited. Consequently, users tend to do trial-and-error experiments that lead to material wastage to achieve higher-quality parts. Therefore, in this study, the manufacturability analysis of various thin wall geometries was performed using carbon-fibre reinforced polylactic acid (CF-PLA) and Wood-based PLA composites. The dimensional accuracy of the fabricated composite parts was then evaluated, inspected and compared with the virgin PLA. The measurements of the printed parts were taken using an image analyser and the deviation between the CAD data and actual data was calculated and compared. The results indicated that the fabricated composite thin wall parts produced better dimensional accuracy with a total error of 0.01 mm for CF-PLA and 0.07 mm for Wood-based PLA. Meanwhile, for virgin PLA, the total calculated error was 0.44 mm. In terms of dimensional accuracy, the thin wall features of the fabricated composite parts showed an improvement of 97.7% and 84.1%, for CF-PLA and Wood-based PLA, respectively, as compared to the virgin PLA. In conclusion, it is suggested to reduce the CAD design by 4% allowance in obtaining very better dimensional accuracy of the composite printed parts.