Our website is currently undergoing maintenance. Article records and full texts remain available. Submissions can be made through the Editorial Manager.

3D Printing of Zirconia Ceramic Slurry: Effect of Overlapping Rate on Surface Finish and Mechanical Properties

J. Zhang, J. Zhou, J. Cai, G. Duan

Journal of Ceramic Science and Technology, Vol. 12, No. 2 (2021), pp. 71-80

DOI: 10.4416/JCST2020-00020

Download full article (PDF)

Abstract

This paper reports on how water-based zirconia ceramic for dentures has been successfully prepared for 3D printing based on a material extrusion process. The rheological properties of the ceramic slurry determine the process parameters, that is the buildability and formed quality of the printed samples. The rheological properties of the zirconia ceramic slurry have been explored to identify suitable process parameters. \"Collapse\" and \"overlapping\" models for the ceramic slurry filament have been developed to underpin the theoretical groundwork for selection of suitable printing parameters. Nozzles with inner diameters measuring 0.4 mm, 0.5 mm, 0.6 mm and 0.7 mm were selected for extrusion tests. The test results showed that, in spite of different nozzle diameters, all the height errors are below 5 %, indicating the rationality for the currently proposed \"collapse\" model. The surface finish and porosity of the printed samples before and after sintering were observed with a digital microscope. Surface roughness, density and mechanical properties of the printing samples were tested and measured. The experimental results show that for the nozzle inner diameter of 0.5 mm, when the overlapping rate of the filaments is set to 6.4 %, in accordance with the currently proposed \"overlapping\" model, the relative density of the printing sample is 0.99; while after sintering, a very desirable roughness of 1.4 μm and bending strength of 611.64 MPa are achieved. The rationality of the currently proposed \"collapse\" and \"overlapping\" models is comprehensively verified by the superior surface quality and mechanical properties of the printed samples. Setting of a suitable overlap rate is helpful for improving the printed quality of ceramic parts. The paper sheds light on precision improvement for 3D printing material extrusion technology in general.

Keywords

Zirconia ceramics, 3D printing material extrusion, filament collapse, overlap rate

View this issue · Article & DOI index