快硬硫铝酸盐水泥在3D打印材料中的应用

将快硬硫铝酸盐水泥(R·SAC)掺加到普通硅酸盐水泥(P·O)中得到混合水泥,以改善P·O 3D打印材料凝结时间长、早期强度低的缺点,系统研究了R·SAC掺量对其凝结时间、力学性能、流动性和堆积性的影响.结果 表明:当R·SAC掺量为14％～20％时,促凝效果明显,有效降低了混合水泥净浆、砂浆的凝结时间,混合水泥净浆的初凝时间可以控制在40～70 min,满足3D打印的要求;掺加R·SAC可以提高材料的流动性,当R·SAC掺量为20％时,混合水泥砂浆的流动度比P·O砂浆提高了11 mm,稠度提高了15 mm;当混合水泥砂浆的流动度在160～175 mm时,可以满足3D打印材料的堆积性要求;掺加少量R·SAC对混合水泥砂浆的早期强度有一定的提升,但是其后期强度有所降低.

Application of Rapid Hardening Sulphoaluminate Cement in 3D Printing Material

By adopting the method of mixing R.SAC with P.O to improve the shortcomings of long setting time and low early strength of P.O 3D printing materials, and the effects of the mixing ratio of P.O and R.SAC on setting time, mechanical properties, fluidity and stacking performance were systematically studied. The results show that: (1) When R.SAC accounts for 14% to 20% of the mixed cement, R.SAC has obvious effect of accelerating setting, and the setting time of cement paste and mortar have been effectively reduced, the initial setting time can be controlled between 40-70 minutes, which meets the requirements of 3D printing. (2) The addition of R.SAC can improve the fluidity of the material. When the mixing ratio is 20%, the fluidity of the mixed cement mortar can be increased by 11mm and the consistency by 15mm compared to the ordinary cement mortar. (3) The fluidity of mixed cement mortar can meet the stacking performance requirements of 3D printing materials within 160 mm to 175 mm. (4) The addition of a small amount of R.SAC has a certain improvement in the early strength of the mixed material, but its later strength has been reduced.