关键词: 3D打印, 无机增稠剂, 硫铝酸盐水泥, 流变性能, 可堆叠性, 力学性能

Abstract: The working performance of 3D printed cement-based materials is a decisive factor affecting their final state. The existing technology mostly uses organic thickeners to regulate its working performance, but there are problems such as reduced strength and high cost. This article selected three inorganic thickeners, namely attapulgite, diatomaceous earth, and sodium based bentonite, to study and compare the working performance and mechanical properties of 3D printed cement-based materials under different thickener dosages. The results show that the working performance of 3D printed cement-based materials improves with the increase of inorganic thickener dosage. The optimal dosage of attapulgite and diatomaceous earth is 2.5% (mass fraction), and the optimal dosage of sodium based bentonite is 1.0% (mass fraction). Among them, sodium based bentonite has the best improvement effect. Different inorganic thickeners also have different effects on the mechanical properties of 3D printed cement-based materials. High dosage of attapulgite has no adverse effect on the strength of 3D printed cement-based materials, diatomaceous earth can enhance the later strength of 3D printed cement-based materials, a small amount of sodium based bentonite can significantly improve the overall strength of 3D printed cement-based materials. The 3D printed cement-based material mixed with 1.0% sodium based bentonite has the best comprehensive performance.

Key words: 3D printing, inorganic thickener, sulphoaluminate cement, rheological property, stackability, mechanical property