基于砂支撑FDM 3D打印的堆砂规律研究

Study on sand stacking law based on FDM 3D printing supported by sand

将颗粒(后面统称砂粒)作为3D打印的支撑材料,避免了传统3轴FDM中因去除支撑而损伤工件的后果。为了归纳出该新型FDM 3D打印技术中的堆砂规律,首先采用Plackett-Burman设计物理实验,选取漏斗孔径X_(1)、漏斗高度X_(2)、漏斗水平移动速度X_(3)以及玻璃砂尺寸X_(4)为参数,研究了砂粒的堆积角规律,其次通过DEM仿真分析了不同漏斗孔径下的砂粒的聚集程度变化。结果表明,参数X_(1)和X_(3)显著影响堆积角,且影响为负效应。随着漏斗孔径的增大,砂粒聚集程度提高。因此在砂作支撑的FDM 3D打印中,增大漏斗孔径可以达到抑制砂道堆积角,提高砂粒堆积聚集性的效果,从而提高工件成型质量。

Particle(hereafter referred together as sand)can be used as the supporting material of 3D printing,which avoid the damage to the workpiece caused by removing the supporting in traditional 3D printing.For concluding the sand stacking law in the new FDM 3D printing technology,this paper designed the physical experiment to search the law of sand’s angle of repose by Plackett-Burman at first,in which the funnel aperture X_(1),the funnel height X_(2),the funnel horizontal moving speed X_(3) and the glass sand size X_(4) were selected as parameters.Secondly,the variation of sand’accumulation degree under different funnel aperture was analysed by DEM simulation.It was found that the aperture of the hopper X_(1) and the horizontal movingspeed of the hopper X_(3) significantly affect the angle of repose,and the influence is negative.Besides,sand’s accumulation degree increases with the increase of funnel aperture.Therefore,in 3D printing supported by sand,increasing the funnel aperture,which inhibit the sand’s angle of repose and improve the sand accumulation,can improve the printing quality.