Investigating the Effect of Modifying the Binder and Other Additives on the Printability of Ceramic Paste for the Direct Ink Writing (DIW) Technique

Ceramic 3d printing, also known as ceramic additive manufacturing, is one of the new production methods based on 3d printers without the need for molds. this manufacturing method allows for the creation of ceramics with complex geometric shapes, hence cost reduction. among the various additive manufacturing methods, extrusion-based printers have been well received by a large number of researchers and industrialists. in this study, the rheological behavior of ceramic pastes and their printability in the extrusion-based 3d printing process were investigated. emphasis is placed on optimizing the parameters that affect paste printing, particularly for pastes containing a high weight percentage (wt%) of alumina powder. the current research used direct ink writing (diw) method to examine the impact of adjusting binder content and additives such as plasticizers and dispersants on the printability of the alumina paste. the results indicate that optimizing these parameters improves the printability of the paste which exhibited shear thinning behavior. paste samples with varying weight percentages of alumina powder and polyvinyl alcohol (pva) binder were prepared. after evaluating their printability and viscosity, the printing process was carried out. the printed samples were then sintered at a temperature of 1250 °c. the results revealed that increasing the printability of alumina pastes enhanced their density and strength. the best results were achieved with a 70 wt% alumina sample, which exhibited a density of 1.8 g/cm³ and a flexural strength of 2.9 mpa. these results confirm the significant influence of wt% of alumina powder on the mechanical properties of the printed parts.