Research on the effect of the waveform on the droplet injection behavior of a piezoelectric printhead and the forming accuracy of casting sand molds

Injection behaviors of printheads are concerned by engineers since they affect the whole working performances and the printing quality of 3D printing device. In view of the quality instability issue for sand molds caused by the fluctuation of the droplet injection performance, a study on the relationship of the driving waveform parameters with the droplet injection performance of a casting sand mold printhead and the printing quality of the sand mold was carried out. Comprehensively considering the applied background of 3D printing in casting sand molds and using the separation of variables method, the quantitative relationship between the driving waveform parameters and the droplet injection characteristics was set up, and the injection performance of the printhead under the current waveform was evaluated through experiments. This article puts forward an optimal waveform for use in casting sand printing. Based on the analysis of existing conclusions, by using special equipment for casting sand mold 3D printing, the printing quality of the sand mold under the new waveform and the current waveform was studied via a comparison experiment. The results show that the new waveform is more suitable for sand mold printing of high-viscosity fluid, as it avoids the presence of satellite droplets. The qualification rate in terms of the sand mold size is enhanced by 44%, and the mechanical properties of the sand mold are effectively improved. This study provides a reliable basis for ensuring dimensional accuracy in the application of 3D printing technology in the precision casting field.