Evolution Rules Of Hygrothermal Properties Of CCF300/Hby8485

Carbon fiber reinforced plastic (CFRP) is the most commonly used as a new and high-performance composite material,however, the role of environmental factor makes the performance of composite limited, hygrothermal environment is one of the most serious conditions. Therefore, the research of evolution rule of CFRP which promote the rational and effective application under hygrothermal environment is an important guarantee and prerequisite.This article prepares CCF300/Hby8485 composite slab by laminate molding,and the surface morphology and micro-morphology of composite under the different hygrothermal environment are observed by IR and SEM. And focuses on the research of moisture absorption of matrix and composite, interfacial properties, static and dynamic mechanical properties, the factors of performance and absorption rules are also analyzed and summarized.The results show that, the absorption process of CCF300/Hby8485 can be divided into three stages. The first stage, the rate of moisture absorption is faster, and based mainly on the infiltration of water concentration; the second stage, moisture absorption based mainly on the matrix; the third stage, the moisture reach saturated,the interfacial of fiber and resin matrix debonds and the micro-cracks of resin matrix expands. In different hygrothermal environment,there are the same trend for the moisture absorption kinetics curve of resin casting and composite. And moisture absorption of CCF300/Hby8485 is physical absorption at 35℃,55℃and 75℃; Invasive and interface between CCF300 and Hby8485 epoxy resin are very well; With the increasing of the moisture absorption time and soaking temperature, flexural strength, compressive strength, interlaminar shear strength and glass transition temperature are all decreased. Especially, the flexural strength and interlaminar shear strength are significantly decreased. And there is the higher retention rate of performance for the composite ,the moisture properties retention of saturated composites which soaked in distilled water of 75℃are separately 64.41% and 65.28%. At the same time, the improving of the soaking temperature will not change the mechanism of composite, only the amplitude is caused by the difference between the performance. Moreover, this conclusion can also be verified by infrared spectroscopy of composite under the different hygrothermal environment; we can know from the surface morphology of fracture cross-section, the higher the soaking temperature is, the longer moisture absorption time is,and the more serious the morphology and interfacial debonding damage, this is consistent with macro-mechanical properties of composite. Moreover, with the the soaking temperature increased slightly, storage modulus of composite decreased gradually.