A comparative study of fabrication of sand casting mold using additive manufacturing and conventional process

In this study, two processes to fabricate casting mold, conventional sand casting process and additive manufacturing or 3D printing process, are comparatively investigated. The two processes were compared in terms of their weight saving, surface finish, design allowance, and fettling work. The results show that there are significant advantages in using additive manufacturing in the production of mold. The 3D printed molds provide substantial saving of sand used, design allowances, and fettling work. The mechanical properties of 3D printed molds are also higher than the conventional ones due to good bonding strength during 3D printing

Extrusion-Based 3D Printing of Molecular Sieve Zeolite for Gas Adsorption Applications

Extrusion based 3D printing is one of the emerging additive manufacturing technologies used for printing range of materials from metal to ceramics. In this study, we developed a customized 3D printer based on extrusion freeform fabrication technique, such as slurry deposition, for 3D printing of different molecular sieve zeolite monoliths like 3A, 4A, 5A and 13X to evaluate their performance in gas adsorption. The physical and structural properties of 3D printed zeolite monoliths will be characterized along with the gas adsorption performance. The Brunauer–Emmett–Teller (BET) test of 3D printed samples will be performed for calculation of the surface area, which will give us the capacity of gas absorption into 3D printed zeolite. The BET surface area test showed good results for Zeolite 13X compared to available literature. The surface area calculated for 3D – printed Zeolite 13X was 767m2/g and available literature showed 498 m2/g for 3D – printed Zeolite 13X. The microhardness values of 3D – printed Zeolite samples were measured using a Vicker hardness tester. The hardness value of the 3D - printed Zeolite samples increased from 8.3 ± 2 to 12.5 ± 3 HV 0.05 for Zeolite 13X, 3.3 ± 1 to 7.3 ± 1 HV 0.05 for Zeolite 3A, 4.3 ± 2 to 7.5 ± 2 HV 0.05 for Zeolite 4A, 7.4 ± 1 to 14.0 ± 0.5 HV 0.05 for Zeolite 5A, before and after sintering process, respectively. The SEM analysis was performed for 3D printed samples before and after sintering to evaluate their structural properties. The SEM analysis reveals that all 3D – printed Zeolite samples retained their microstructure after slurry preparation and also after the sintering process. The porous nature of 3D – printed Zeolite walls was retained after the sintering process

Optimization of Printing Parameters for 3-D Printed PLA

In this work, 3D printed part of PLA was checked for dimensional accuracy and printing parameters were optimized for getting optimal design. For doing so we selected nozzle temperature and step size as printing parameters for optimization. Design of Experiment (DOE) was done using Minitab to check optimal parameters. We concluded that increasing the nozzle temperature increases the dimensional accuracy of the printed part and decreasing the step size will increase the dimensional accuracy

Slurry Preparation of Zeolite and Metal-Organic Framework for Extrusion Based 3D-Printing

Extrusion-based 3D printing is one of the emerging additive manufacturing technologies used for printing a range of materials from metal to ceramics. In this process, the required material is extruded from the extruder in the form of a slurry. Zeolite and MOFs are mainly used for CO2 adsorption in the form of pellets and beads due to their good adsorptive property. Researchers are developing monoliths of Zeolite and MOFs and fabricate them using traditional extrusion and implement them in the gas adsorption applications as an option for beads and pellets by developing a monolithic structure. Previous research on Zeolite 13X and 5A have shown good structural and physical properties in monolith form. In this study, we developed slurry of two molecular sieve Zeolite 3A and 4A monoliths powders, mixing it with bentonite clay, methyl cellulose, and PVA as a binder. The slurry preparation was carried out at room temperature. Once the 3D printed samples are dried at room temperature, a sintering process was performed to increase mechanical strength. To be used in realtime applications, the 3D printed Zeolite sample need to have sufficient mechanical strength. The BET surface area test showed good results for Zeolite 13X compared to available literature. The surface area calculated for 3D printed Zeolite 13X was 767m2/g and available literature showed 498 m2/g for 3D printed Zeolite 13X. The microhardness values of 3D printed Zeolite samples were measured using a Vicker hardness tester. The hardness value of the 3D-printed Zeolite samples increased from 8.3 ± 2 to 12.5 ± 3 HV0.05 for Zeolite 13X, 3.3 ± 1 to 7.3 ± 1 HV 0.05 for Zeolite 3A, 4.3 ± 2 to 7.5 ± 2 HV0.05 for Zeolite 4A, 7.4 ± 1 to 14.0 ± 0.5 HV0.05 for Zeolite 5A respectively. The SEM, EDS and XRD analysis was performed for 3D printed samples before and after sintering to evaluate their structural properties. The SEM analysis reveals that all 3D printed Zeolite samples retained their microstructure after slurry preparation and also after the sintering process. The porous nature of 3D printed Zeolite walls was retained after the sintering process. The EDS analysis showed that the composition of 3D printed Zeolite samples remained somewhat similar with minor variation for before and after sintering. The framework structure of Zeolite Type X for Zeolite 13X and Zeolite Type A for Zeolite 3A, 4A, 5A were in good shape after sintering as standard peak intensity points were retained. Zn-MOF74 was synthesized using solvothermal synthesis which is a well-established synthesis process used for the synthesis of MOFs. We also developed slurry for Zn-MOF-74 using bentonite clay and PVA as binders and printed small parts using hand printing