C_(uf)/铝硅酸盐聚合物复合材料的制备和力学性能

Preparation and Mechanical Properties of Carbon Fiber Reinforced Geopolymer Composites

通过超声辅助-料浆浸渍工艺制备单向碳纤维强韧不同硅铝比铝硅酸盐聚合物(Si/Al=2,2.5,3,3.5和4)复合材料,研究硅铝比对铝硅酸盐聚合物和复合材料力学性能和断裂行为的影响。结果表明,复合材料中碳纤维能够被充分浸渍并且复合材料具有均匀的组织结构。随Si/Al的提高,铝硅酸盐聚合物和复合材料的弯曲强度和弹性模量均逐渐增加,但是复合材料的断裂功首先增加,并在Si/Al=3时达到峰值,然后逐渐降低。所有的复合材料均表现出非灾难性断裂行为,并且Si/Al<3的复合材料以剪切断裂模式为主,而Si/Al>3的复合材料呈现弯曲断裂模式。在Si/Al≥3的复合材料中能够观测到大量的纤维拔出,表明碳纤维显著的强韧作用。

Unidirectional carbon fibre reinforced geopolymer matrix composites were prepared by a simple ultrasonic-assisted slurry infiltration method. Mechanical properties and fracture behaviour of the composites were systematically studied. Carbon fibre fabrics were fully infiltrated with geopolymer resin in all the composites. With increasing Si/Al ratio, flexural strength and Young’s modulus of the composites is increased gradually due to the increased strength and stiffness of geopolymer resin. While work of fracture increase first, and get the peak value in the composites with Si/Al=3, and then decreases gradually. All the composites reinforced with carbon fibre show non-catastrophic fracture behaviour. Composites with Si/Al < 3 fracture in shear fracture mode, while those with Si/Al > 3 fracture in tensile fracture mode. Meanwhile, considerable fiber pull-out is observed in composites with Si/Al≥3, indicating the significant reinforcing effects of carbon fibers in these samples.