An investigation on impact resistance of FDM processed Nylon-12 parts using response surface methodology

Abstract

Fused Deposition Modelling (FDM) is one of the leading additive manufacturing processes for plastic part manufacturing. However, engineers often face difficulties to specify the actual levels of process parameters in FDM process to achieve the proper mechanical properties of FDM fabricated parts. The effect of large number of FDM process parameters and the interaction among them need to be understood to achieve desired level of mechanical performance. This paper presents a study on the influence of three FDM process parameters (air gap, raster angle, and build orientation) on the impact strength and mechanical properties of the FDM Nylon 12 fabricated parts by Fortus 450mc FDM machine. The Response Surface Methodology (RSM) based on face centered central composite design was used to analyse, validate, and optimize the results. The significance of parameters was statistically validated with the analysis of variance (ANOVA) technique. The results show that the part build Y-orientations (flat) at 0° and 45° have a significant directly proportional influence on the impact strength, while Z-orientation (upright) at 90° has indirectly proportional effect on the impact strength. Moreover, raster angle has a much significant directly proportional influence on the impact strength at 0° and 60° angles and indirectly proportion influence at 30°.