Development of Process Model for Optimal Selection of Process Parameters for Geometric Tolerances and Surface Roughness in Stereolithography

The accuracy of stereolithography (SL) product is vital for meeting the intended functional applications. The parameters like layer thickness, hatch spacing, hatch overcure contribute significantly to the accuracy of the SL parts. In this paper an attempt has been made to identify the process parameters that influences on the accuracy of the parts made with CIBA TOOL 5530 and optimize the process parameters. A standard test specimen is designed for this study. A process model between the geometric tolerance (parallelism, perpendicularity, angularity, radius fillet), surface roughness and the above mentioned process parameters (layer thickness, hatch spacing, hatch overcure) have been developed. It is found that parallelism, perpendicularity, angularity, radius fillet and surface roughness are influenced significantly by hatch spacing, layer thickness, hatch overcure, hatch spacing and layer thickness respectively. The percentage deviation between the experimental and process model values have also been calculated to validate the developed process model.