Characteristics of photopolymeric material used in rapid prototypes: Part I. Mechanical properties in the green state

Abstract

The curability and mechanical properties of an acrylic-based photopolymer (namely De Solite SCR-300) used in building rapid prototypes have been studied. A differential scanning calorimeter (DSC) was used to monitor the degree of curing of the resin after laser scanning. It was observed that the curability of the resin in the stereolithography process was a function of layer pitch and laser exposure density. Tensile tests were conducted on multi-layered specimens generated under different layer pitch and laser exposure density. It was found that the elastic modulus, ultimate tensile strength and elongation to fracture of the specimens were also functions of laser exposure density and layer pitch. Morphological tests using a scanning electron microscope (SEM) showed changes in the cross-sectional profile of a multi-layer model with laser exposure density and layer pitch. By increasing the laser exposure density and decreasing the layer pitch, the curing percentage of the resin can be increased, leading to a prototype built with better mechanical strength. © 1997 Elsevier Science S.A.