短碳纤维的分散性对CFRC力学性能的影响

碳纤维增强水泥基复合材料(CFRC)是一种新型建筑智能材料,碳纤维在水泥基体中的分散性直接影响着它的力学性能.借助超声波和甲基纤维素(MC)分散剂,实现了短碳纤维在水泥基体中的均匀分散,对所制备的CFRC复合材料的断口形貌作了SEM观察;测试了试件的抗压强度、抗拉强度和抗折强度.结果发现,碳纤维均匀分散时,复合材料的抗压强度提高19%,抗拉强度比不加碳纤维时提高2.2倍,弹性模量提高1.4倍.此外,复合材料的抗弯强度、抗折强度均高于未均匀分散时的强度.

Effect of Dispersion of Short Carbon Fibers on the Mechanical Properties of CFRC Composites

Carbon-fibre-reinforced cement-matrix composites (CFRC) is a new kind of building smart material. The dispersion of carbon fibers in the matrix affects its mechanical properties directly. With the help of ultrasonic wave and dispersant methyl cellulose (MC), the even dispersion of short carbon fibers is realized. The fracture surface of CFRC is observed by scanning electron microscopy (SEM). The flexural strength, tensile strength, and compression strength are measured. Results show that the compressive strength increases by 19%, the tensile strength of the composites reinforced by carbon fibers is 2.2 times that of the cementitious material without carbon fibers and the modulus 1.4 times. Additionally, the flexural strength and the bending strength are improved when carbon fibers are dispersed uniformly.