纳米金属氧化物对水泥基材料力学性能的增强效应

为了区别6种纳米金属氧化物(Al2O3、CuO、ZrO2、MgO、Fe3O4和Fe2O3)对水泥基材料力学性能的贡献。通过等质量替代(2%和4%)水泥,制备水泥基材料,测试其力学性能。结果表明：纳米Al2O3、CuO、ZrO2、MgO、Fe3O4和Fe2O3均能提高水泥基材料的抗折强度和抗压强度,纳米ZrO2的增强作用最大,28d~90d时分别为34%~47%和28%~51%,纳米CuO的增强作用最小,28d~90d时分别为4%~9%和4%~10%。通过影响系数和增长速率的计算发现,6种金属氧化物对水泥基材料的促进作用主要集中在28d前,28d后的促进作用不明显。分析认为,6种纳米金属氧化物在水泥基材料中主要发挥填充作用,晶核作用和表面活性作用,达到促进水泥颗粒水化、提高其密实度和力学性能的目的。

Enhancement effect nano-metal oxide on mechanical properties of cement-based materials

In order to distinguish the contribution of six nano-metal oxides (Al2O3, CuO, ZrO2, MgO, Fe3O4 and Fe2O3) to the mechanical properties of cement-based materials. Cement-based materials were prepared by replacing (2% and 4%) cement with equal mass and testing its mechanical properties. The results show that nano-Al2O3, CuO, ZrO2, MgO, Fe3O4 and Fe2O3 can all improve the flexural strength and compressive strength of cement-based materials. The nano-ZrO2 has the greatest enhancement effect, which is 34% to 47% and 28%~51% at 28d~90d, the enhancement effect of nano-CuO is the smallest, which is 4%~9% and 4%~10% at 28d~90d, respectively. Through calculation of influence coefficient and growth rate, it is found that the promotion effect of six metal oxides on cement-based materials is mainly concentrated before 28d, and the promotion effect after 28d is not obvious. According to the analysis, the six nano-metal oxides mainly play a filling role, crystal nucleation and surface activity in the cement-based materials, thereby promoting the hydration of the cement and improving the compactness of the cement-based materials, thereby achieving the purpose of increasing their mechanical properties.