Effect of Sizing Agents on Surface Properties of T800 Grade CF and Thermal Aging Time on Mechanical Properties of T800 Grade CF/Epoxy Composites

Abstract

This paper investigates the effect of sizing agent molecular weight on carbon fiber (CF) surface properties and the effect of thermal aging time on mechanical properties of CF/epoxy composites. The surface properties of three CCF800 CF samples with varying sizing agent molecular weight were characterized by surface morphology, surface roughness, chemical functional groups, and element composition. The results showed that the sample with low molecular weight exhibited low roughness and high proportion of activated carbon atoms. The flexural strength, flexural modulus, and interlaminar shear strength of CCF800/5228 composites were measured at 25°C and 150°C by thermal ageing time 0, 100 h, 250 h, 500 h, and 1000 h. The results showed that the thermal aging time up to 1000 h had little effect on the flexural modulus, and the interlaminar shear performance at 150°C showed a trend of increasing at the beginning and then decreasing.

Grey model prediction for the interfacial properties of carbon fiber-reinforced bismaleimide resin under thermo-oxidative aging

“…We can obviously find that the sequence of x ( 1 ) ( k ) varies exponentially with time, and thus the corresponding whitening differential equation is where a and u are the development coefficient of the system and endogenous control grey scale, respectively.…”

“…The modeling mechanism of GM (1,1). By fully developing and utilizing the explicit and implicit information in the existing data, the randomness that is present in the series is cumulatively weakened.…”

“…We can obviously find that the sequence of x (1) (k) varies exponentially with time, and thus the corresponding whitening differential equation is…”

“…High-performance fibers, such as carbon fiber (CF)-reinforced thermostable resin composites, have been widely used as components in the hot end components of aeronautics and astronautics because of their light weight, excellent strength/stiffness and thermal resistance. 1,2 In many applications, such as aeronautical components, one of the greatest concerns is associated with the long-term aging effect. 3 For instance, CF-reinforced polymer composites (CFRPCs) exposed to a high temperature for a long time results in a change of their structure and size, and finally reduces the reliability and lifetime of aircraft in service.…”

Influence Mechanism of Rubber Thermal Oxygen Aging on Dynamic Stiffness and Loss Factor of Rubber Isolation Pad

“…The effect of the thermal oxygen aging factors on the rubber materials was not taken into consideration in the above studies, then some scholars began to study the effect of rubber thermal oxygen aging on the mechanical performances [13,14]. Nie et al [15] conducted an experimental analysis of the thermal oxygen aging and the mechanical fatigue on natural rubber under the different fillers' matrix, and the aging mechanism of rubber was analyzed from the aspects of crosslink density and defects content, which provided a theoretical basis for modeling the mechanical characteristic of rubber with the thermal oxygen aging condition.…”