On the use of stereolithography built photoelastic models for stress analysis investigations

When designing mechanical components, it is essential to investigate and provide crucial information for mechanical failure due to stress generation. Photoelasticity and numerical methods are well known for stress determination and design evaluation purposes. The rapid-prototyping technique of stereolithography allows complex models of components to be built, in a matter of hours, out of photoelastic resins. The objective of this study was to evaluate the feasibility of a commercially available epoxy-based photopolymer for photoelastic investigations. A number of experiments were undertaken to address critical material and fabrication issues related to stereolithography built photoelastic specimens. The data gathered from photoelastic model testing was compared to the ones generated by numerical analysis. The good correlation between them in terms of measured and calculated magnitudes of stress provide increased confidence in the investigated photopolymer for photoelastic stress analysis purposes, and consequently for validation of computer-based models, utilizing thus stereolithography models as complementary design tools.