3D打印模拟月壤道路材料制备与性能研究

In order to prepare road materials with lunar soil simulant that can be used for 3D printing and to initially explore the technology of in-situ lunar resource utilization, geopolymer slurry based on BH-1 lunar soil simulant with a water-ash ratio of 0. 28-0. 32 was used as the printing ink, and the flow curves of the slurry were tested at the printing temperature of 40 "C-80 °C using dynamic shear rheological tests. Two rheological parameters, yield stress and plastic viscosity, were obtained by fitting the Bingham model. The upward flow curve and downward flow curve were calculated, obtaining the thixotropic ring area to characterize the shear damage properties of the material. The of the slurry were investigated using the feeding mechanism of the 3D printing machine. The relationship between the two workability and the rheological parameters was determined. A test method for extracting 3D point clouds on the surface of 3D printed specimens using a 3D contour scanner, and then obtaining the overall material deformation and surface texture, was proposed to quantitatively evaluate the buildability of the material. Finally, the effects of different filling rates on the mechanical properties and printing efficiency of 3D printed specimens were investigated. The results show that the BH-1 geopolymer slurry is of shear thinning characteristics. The yield stress and plastic viscosity coefficient decrease with increasing water-ash ratio, increase with resting time. And the higher the printing temperature, the faster the lifting speed. The upper limit of yield stress is 1090 Pa and the plastic viscosity is 11. 5 Pa • s for successful extrusion. The larger the water-ash ratio, the lower the printing temperature, the stronger the extrudability of the materials and the longer the construction time. Raising the printing temperature is beneficial to enhance the buildability of the material. In all test groups, a water-ash ratio of 0. 32 and a printing temperature of 80 °C can effectively control the deformation of the printed specimens while satisfying the extrudability and a longer open time limit. Reducing the filling rate leads to a decrease in the mechanical properties of the material but can enhance the 3D printing speed and save material.