Experimental and statistical investigation on flexural properties of FDM fabricated PLA specimens applying response surface methodology

Additive manufacturing (AM) is a modern technology currently adopted by manufacturing industries to benefit from its low-cost applications, versatility and fabrication of complex parts. Fused deposition modeling (FDM) is distinguished among the different AM technologies due to its fast, yet accurate operations. However the properties of fabricated components are strongly depended by FDM-related parameter settings. This work examines the effect of FDM-related parameters namely flow rate, printing speed and printing temperature on the response of flexural strength. Experiments according to L9 orthogonal array and a custom response surface experimental design were performed to obtain the results necessary for further examination and analysis corresponding to parameter effects on flexural strength and statistical outputs. Experiments were designed as per the ASTM D790 standard whilst failure modes of experimental samples were observed for correlating the independent printing parameters with the response of flexural strength. The full quadratic regression model generated for predicting results concerning flexural strength was found adequate for explaining the variation of FDM-related parameters on flexural strength response.