Enhancing Tensile Strength in 3D-Printed Parts with Embedded Epoxy

3D printing has been used as a transformative technology in various industries for customization and prototyping of complex designs in real-world scenarios. This study explores commonly used 3D printing materials (PLA and ABS) to verify our hypothesis that the addition of epoxy in the voids during printing will improve the tensile strength of 3D-printed samples. Using ASME standard dog-bones (L=165 mm, W= 19 mm, t = 5 mm) designed in SolidWorks and printed to conduct porosity tests and tensile strength loading for two epoxies (MG Chemicals 1:1 Ratio 832HG epoxy and GH1200 Super Glue). The printed samples had the following in-fill percentages: 20%, 40%, 60%, and 100%. The fluid displacement method (porosity test) was used to make porosity measurements, showing that at 20% fill, the average porosity is about 21.55%; at 40% infill, the average porosity goes down to about 11.94%; and at 100% infill, the average porosity falls drastically to 4.80%. Experimental results show that porosity decreased for the samples that were embedded with epoxy. To carry out the tensile strength experiments, a special protocol was developed. The printing was paused halfway to add epoxy into the voids between the layers, allowing the samples to cool for 15-30 minutes for epoxy solidification before resuming. Testing was carried out with an Instron 1KN machine. Our preliminary results do indicate a slight increase in the tensile strength of the epoxy-embedded samples. This trend was constant across samples that were printed at various infill factors. These results are encouraging but need further research to ensure that filling the pores partially within the printed material does enhance the tensile strength in a predictable manner at various operating conditions.