Influence of alumina particles (AL2O3) on physico-mechanical behavior of additive manufacturing- DLP resin used for rapid tooling

Over the past decade, additive manufacturing (AM) has gained considerable recognition in rapid tool manufacturing owing to its notable advantages. For the rapid injection mold manufacturing by the DLP-AM method, the most important subject that should be focused on is the photopolymer resin, as the 3D printed mold must withstand the stresses and temperatures encountered by the in jection pressure and temperature of the molten plastic. This study aimed to investigate the effect of adding alumina (Al2O3) powder on the properties of a DLP-AM photopolymer. For this aim, 2 and 4 wt.o/o Al2O3 were added to a photopolymer resin, and 3D-printed samples were produced by DLP. Several physico-mechanical properties were studied compared to the pure polymer. The results indicated that as the Al2O3 content increased, the void fraction, volumetric heat capacity, wear resistance, tensile and flexural strength, all decreased. In contrast, as the Al2O3 wt.o/o increased, so did the flexural strain, impact strength, hardness, and thermal conductivity. This study showed that injection molding cycle times can be shortened considerably due to this benefit, which would be beneficial for quick molding applications.