Experimental and Statistical Modeling for Effect of Nozzle Diameter, Filling Pattern, and Layer Height of FDM-Printed Ceramic–Polymer Green Body on Biaxial Flexural Strength of Sintered Alumina Ceramic

Abstract

This paper deals with the application of statistical analysis in the study of the dependence of the flexural strength of sintered alumina (Al2O3) disks on the parameters (nozzle diameter of the printer print head, layer height, and filling pattern) of the fused deposition method (FDM) printing of ceramic–polymer filament containing 60 vol.% alumina and 40 vol.% polylactide. By means of a correlation analysis applied to the results of flexural tests, a linear relationship was found between the thickness of the printed layer and the strength of the sintered specimens. A statistically significant linear relationship was found between the geometric parameters and the weight of both printed ceramic–polymer and sintered ceramic samples, as well as the diameter of the nozzle used in the printing of the workpiece. It was found that the highest strength is achieved with a layer thickness equal to 0.4 mm, and the smallest scatter of mass values and geometric dimensions of ceramic samples is achieved using a nozzle diameter of 0.6 mm. As a result of the conducted research, linear equations allowing the prediction of changes in the geometry and mass of samples after sintering, as well as the strength properties of sintered samples, taking into account the geometry and mass of FDMed samples, were obtained.