Analysis of the Mechanical Properties and Damage Mechanism of Carbon Fiber/Epoxy Composites under UV Aging

Abstract

The UV durability of carbon fiber composites has been a concern. In this work, UV irradiation on carbon fiber-reinforced polymer (CFRP) materials was performed using an artificial accelerated UV aging chamber to investigate the effect of UV exposure on carbon fiber composites. UV aging caused some of the macromolecular chains on the surface resin to break, resulting in the loss of small molecules and loss of mass. After 80 days of UV irradiation exposure, a significant decline in the macroscopic mechanical properties occurred in the longitudinal direction, with the largest decrease of 23% in longitudinal compressive strength and a decreasing trend in the transverse mechanical properties at the later stage of aging. The microscopic mechanical properties of the CFRP specimens were characterized using nanoindentation, and it was found that UV aging had an embrittlement effect on the matrix, and its hardness/modulus values were higher than the initial values with UV exposure. The fibers were less affected by UV irradiation.

Recyclable, Repairable, and Fire-Resistant High-Performance Carbon Fiber Biobased Epoxy

“…Then, in the DSC curve of the CF composite (Figure S4) two T g s appear distinctly, confirming that a secondary transition occurs. Glass transition values superior to the DGEBA based carbon fiber composites reported in the literature (63–120 °C) ,− and comparable to that of the composite developed in this work are specified for commercial laminates such as Solvay CYCOM 890 RTM Resin-Woven Carbon Fabric Composite: T g = 169–210 °C; Polynt 90 CF40-400g Carbon Fiber Epoxy Fleece: T g = 150–200 °C; Solvay CYCOM 934 Epoxy-Carbon Fiber Reinforced Laminate: T g = 160–194 °C; or Park Aerospace Nelcote E-746 Epoxy Prepreg, 3k 5HS Carbon Reinforced: T g = 180–230 °C.…”

Contributing Factors of Uneven Climatic Aging for Polymeric Composite Materials: Methods and Modelling

“…Similar effects were found for CFRP IM7/997 [ 59 ], GFRP based on epoxy and polyester matrices [ 60 , 61 ], CFRP AS4/8552 [ 62 ], and CFRP based on T700 fiber [ 63 ]. In all cases, a decrease in mechanical properties of PCM is accompanied by damage at the polymer-filler interface and microcracks.…”

“…If thermal and moisture exposure is accompanied by UV irradiation, its simultaneous or alternate exposure significantly increases the likelihood of microcrack formation. This regularity was confirmed in [ 57 , 58 , 59 , 60 , 61 , 62 , 63 ].…”

Strength Characteristics of Carbon Fiber Reinforced Plastic in Shear and Cyclic Extension-Compression after 7 Years of Climate Exposure

“…Exposure of CFRP in open climatic conditions according to the data of [20,21] showed that as a result of exposure to temperature, freezing-thawing processes, marine chlorides in the air, aging occurs, accompanied by a change in mechanical properties. According to Shi et al [22] CFRP aging grows under the influence of the ultraviolet component of solar radiation.…”