In order to use the material's rheological properties to adjust and optimize the process parameters of 3D printed cement-based materials. The rheological properties of cementitious materials are tested at different settling times with the same ratio. The 3D printing speed (extrusion speed and feed speed) is analyzed based on the 3D printing strip molding accuracy. The test results are indicated as follows. Within the group of seven with settling time for 10 min, 30 min, 50 min, 60 min, 70 min, 80 min and 100 min, the yield stress and plastic viscosity increases with increasing settling time of the freshly mixed cementitious material. The width of the print strips decreases with increasing rheological parameters when the printing speed is fixed. The width of the print strips increases with the increasing the extrusion speed when the rheological parameters and the feed speed are fixed. The width of the print strip decreases as the feed speed increases when the rheological parameters and extrusion speed are fixed. In addition, the feed speed has a greater impact on the uniformity of the print strip, and the extrusion speed only affects the width of the print strip. There is linear correlation between plastic viscosity, static yield stress and extrusion speed, the plastic viscosity has the strongest positive correlation with extrusion speed. The ratio of optimal extrusion speed to optimal feed speed is stabilized between 4 and 5. Therefore, the optimal printing speed can be determined by testing the rheological properties of the material.
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