摘要
磷酸镁水泥基材料具有快硬早强的特点,适用于水泥基粉末3D打印技术。为解决粉末3D打印磷酸镁水泥耐水性能差的问题,本文开展了粉末3D打印磷酸镁水泥基材料耐水性能优化研究,研究了镁磷比对材料耐水性能的影响,优选了镁磷比(摩尔比,下同),探究了粉煤灰掺入对粉末3D打印磷酸镁水泥基材料打印性能和耐水性能的影响规律,并结合微观表征手段揭示了粉煤灰对材料耐水性能改善机理。结果表明:粉末3D打印磷酸镁水泥基材料在水养护条件下的抗压强度降低;随着镁磷比的增加,材料耐水性能相应提高;添加粉煤灰可有效提高粉床密度和打印精度,增加材料的水化产物生成量,使微观结构更加致密,提高其耐水性能;材料浸水28 d后掺入20%(质量分数)粉煤灰可使材料的抗压强度最大提高89.00%,这为改善粉末3D打印磷酸镁水泥基材料的耐水性能及拓展水泥基粉末3D打印技术的应用提供了有力支撑。
Magnesium phosphate cement-based material has the characteristics of fast hardening and early strength,which is suitable for cement-based powder bed 3D printing technology.In order to solve the problem of poor water resistance of powder bed 3D printing magnesium phosphate cement,the optimization of water resistance of powder bed 3D printing magnesium phosphate cement-based materials was carried out.The influence of M/P molar ratio on water resistance of materials was studied,and M/P molar ratio was optimized.The effect of fly ash incorporation on the printing performance and water resistance of powder bed 3D printing magnesium phosphate cement-based materials was studied,and the mechanism of fly ash improvement on water resistance of printing materials was revealed by combining the microscopic characterization methods.The results show that the compressive strength of powder bed 3D printing magnesium phosphate cement-based materials decreases under water curing condition.With the increase of M/P molar ratio,the water resistance of specimen is improved accordingly.The addition of fly ash can effectively improve the density and printing accuracy of the powder bed,increase the amount of hydration products,make the microstructure more dense,and improve the water resistance of specimen.By adding 20%(mass fration)fly ash,the compressive strength of materials increases by 89.00%at most after 28 d of water immersion,which provides strong support for improving the water resistance of powder bed 3D printing magnesium phosphate cement-based materials and expanding the application of cement-based powder 3D printing technology.
作者
刘晓江
李之建
LIU Xiaojiang;LI Zhijian(School of Civil and Transportation Engineering,Hebei University of Technology,Tianjin 300401,China)
出处
《硅酸盐通报》
CAS
北大核心
2024年第5期1673-1682,共10页
Bulletin of the Chinese Ceramic Society
基金
国家自然科学基金(52108205)
“十四五”国家重点研发计划子课题(2023YFC3806901)。
关键词
磷酸镁水泥
粉末3D打印技术
耐水性能
力学性能
粉煤灰
magnesium phosphate cement
powder bed 3D printing technology
water resistance
mechanical property
fly ash
