Forming quality evaluation of 3D printed lines and layers with cement-based materials under different process parameters

Purpose 3D printing with cement-based materials is rapidly developing globally, demonstrating its ability to construct large-scale components or even buildings. The purpose of this study is to investigate the influence of various process parameters on forming quality of cement-based materials. Design/methodology/approach This study used a self-developed 3D printing apparatus to evaluate the forming quality of printed lines and layers with cement-based materials under different process parameters. Layer height, nozzle traveling speed, material extrusion flow rate and overlap width were identified as the main process parameters. To evaluate the forming quality of printed lines and layers, the quantitative indicators of line width variance and maximum height difference were proposed. Findings The average variance of line width decreased first and then increased with the increase of nozzle traveling speed. When the nozzle traveling speed was between 8000 and 8500 mm/min, the average variance was relatively small, ranging from 0.31 to 0.67, indicating better forming quality of the printed lines. The maximum height difference gradually decreased as the overlap width decreased, indicating better surface smoothness. When the overlap width was 3 mm, which is 0.2 times the nozzle diameter, the maximum height difference ranged from 1.90 to 3.88 mm, and the forming quality of the printed layers was better. Originality/value The research results could provide references for evaluating the forming quality of 3D printing cement-based materials.