DETERMINING THE INFLUENCE OF LAYER THICKNESS FOR RAPID PROTOTYPING WITH STEREOLITHOGRAPHY (SLA) PROCESS

摘要

Stereolithography is a Rapid prototyping technique, which allows direct transformation of CAD files into epoxy resin parts for building the physical models, these are built from photo-curable thermosetting resins. Part quality in the Stereolithography process is a function of the build parameters such as hatch cure depth, layer thickness, orientation and hatch file. This paper attempts to identify and study the various process parameters governing the stereolithography system, specifically the influence of layer thickness related to the part characteristics. The part characteristics can be divided into part physical characteristics and mechanical characteristics. The part physical characteristics are surface finish, dimensional accuracy and distortion where as mechanical characteristics are flexural property, ultimate tensile strength and impact strength. Thus paper proposes to study the influence of the layer thickness (build parameters) over the part quality. The study is conducted on the test samples of SL 5530, which were built on SLA5000 machine, under different sets of process parameters and tested under ASTM specified test conditions. The results have been analyzed to achieve an optimal layer at which the mechanical properties are high with minimum dimensional instability, which is found to be 100 micron layer thickness. To obtain an optimal layer thickness for the SLA parts is the end result of the paper.