矿物掺合料对3D打印水泥基材料性能的影响

Effect of Mineral Admixture on Properties of 3D Printing Cement-Based Materials

通过将粉煤灰和硅灰分别以单掺及复掺形式掺入3D打印水泥基材料中,研究其对打印材料工作性能及力学性能的影响。结果表明:粉煤灰的掺入能够提高打印材料的流动度,但降低其可建造性;而硅灰的掺入效果则相反;不论单掺还是复掺,矿物掺合料的加入均会导致打印材料凝结时间出现不同程度延长;对于力学性能,粉煤灰的掺入会导致打印材料的抗压和抗折强度降低,而硅灰的掺入则会提高其力学性能;通过打印试样与浇筑试样的力学性能对比发现,由于打印工艺缺陷导致相邻打印长丝之间结合欠佳,产生孔隙,使得打印试样的强度低于浇筑试样,尤其对抗压强度影响显著。

The fly ash and silica fume were separately added into 3D printing cement-based materials in the form of single and mixed,and their effects on the working and mechanical properties of printing materials were studied.The results show that the addition of fly ash increases the fluidity of the printing materials,but reduces its buildability,while the effect of silica fume is opposite.Whether single or mixed,the addition of the mineral admixture causes the setting time of printing materials prolonged on different degrees.As for mechanical properties,the addition of fly ash decreases the compressive and flexural strengths of the printing materials,while the addition of silica fume increases its mechanical properties.Comparing the mechanical properties of the printing and cast sample,due to the printing process defects,the bonding between adjacent printed filaments is poor and the pores are produced,which result in the strengths of the printing sample lower than that of the cast sample,especially the compressive strength.