Analysis of the Effects of 3DP Parameters on Part Feature Dimensional Accuracy

Abstract

3D printing (3DP) is a widely investigated scaffold manufacturing process for Tissue Engineering (TE). Useful scaffold geometries should have high porosity (60-80%) with small (100-500 μm) interconnected pores. Therefore dimensional accuracy on the micron level is one of the crucial parameters of the bone scaffolds. Previously it was shown that the behavior of scaffold geometries can be well simulated with Finite Element Modeling (FEM) however the prediction of actual strength and stiffness values are dependent on dimensional accuracy. This accuracy is in turn dependent on several parameters including particle size and shape, powderbinder interaction, and machine setup. In this work different scaffold strut sizes (0.3 - 0.5 mm) have been fabricated using two different plaster powders (zp102 and zp130) with variations in shell saturation levels, part print position, and part print orientation. The parameters for each powder were analyzed using a full 35 factorial experimental design. It was found that the part size and orientation had a significant effect on the dimensional accuracy while the influence of the shell saturation and position was relatively small. The results allow for better dimensional specification for scaffold geometry fabrication by defining the process parameters in 3DP that may be used further in scaffold accuracy optimization.