碳纤维增强树脂复合材料细观蠕变性能

碳纤维增强树脂复合材料以其优异的性能，在各领域得到广泛应用。由于树脂基体具有黏弹性，使其合成的复合材料也表现出黏弹性行为。蠕变是材料黏弹性行为中最典型的一类现象，因此对碳纤维增强树脂复合材料细观蠕变性能的研究具有重要意义。室温下利用纳米压痕技术对碳纤维增强树脂复合材料中的基体、界面及纤维相在不同峰值载荷下的细观蠕变行为进行分析。结果表明:在相同的蠕变时间下，最大载荷为2 mN和10 mN的纤维蠕变位移约为基体蠕变位移的1/3和1/2，界面的蠕变位移介于两者之间；稳态蠕变阶段的蠕变速率小于0.1%；基体、界面、纤维的蠕变应力指数分别为3.6、2.9和2.1。同时根据Kelvin-Voigt模型得到了基体、界面及纤维的第一、第二复数模量、黏度系数及蠕变柔量。 

Microcreep properties of carbon fiber reinforced resin composites

Carbon fiber reinforced resin composites are widely used in various fields because of their excellent performance. Since the resin matrix has viscoelastic properties, the composite material synthesized by resin also exhibits viscoelastic behavior. Creep is the most typical type of phenomenon in the viscoelastic deformation, so it is of great significance to study the microcreep properties for carbon fiber reinforced resin composites. Under different peak loads, the microcreep behavior of the resin matrix, interface and fiber for carbon fiber reinforced resin composites were analyzed by nanoindentation technique at room temperature. At the same creep time, the results show that the creep displacements of the fibers which are about 1/3 and 1/2 of the matrix under 2 mN and 10 mN. And the values of interfacial creep displacements are between the fiber and the matrix. The creep rate of steady state creep stage is less than 0.1%. The creep stress indexes of the matrix, interface and fiber are 3.6, 2.9 and 2.1. The first and second complex modulus and the viscosity of the dashpot and creep complicement for the matrix, interface and fiber were obtained using the Kelvin-Voigt model at different peak loads.