High modulus carbon fibre composites: Correlation between transverse tensile and mode I interlaminar fracture properties

Abstract

This paper presents test results from mode I interlaminar fracture and transverse tensile tests on unidirectional carbon/epoxy composites used in racing yacht construction. Fibre modulus has been varied from 380 to 640 GPa. PAN fibre reinforced composite properties, delamination resistance (GIc and GIp) and transverse strain to failure, decrease as fibre modulus increases. Composites based on the highest modulus pitch fibres show higher transverse failure strains than the highest modulus PAN fibre composites. A distinct failure mechanism, crack propagation within the fibres, was observed for the pitch based reinforcement. The transverse tensile tests allowed transverse fibre modulus to be estimated as 11.5 GPa for the PAN and 9 GPa for the pitch fibres. These results indicate that more detailed study is needed if pitch based composites are to be optimised.

Identification and evaluation of progressive thermal degradation caused by carbamate formation in cyanate ester resin‐based composites

“…The samples were cured with the standard process and then post‐treated to 200°C for an additional 4 h. The initial T g for the control sample was ∼230°C with a flatwise tensile strength of ∼14.5 MPa. This is a typical value reported for the through‐thickness flatwise tension value for a composite using this very high modulus Pan‐based carbon fiber [31, 32]. As shown, the matrix‐dominated flatwise tensile strength correlates quite well with glass transition temperature of the composite as a function of initial moisture content.…”

Microcracking Study of Carbon Fiber Composite Materials for Starshade Petals

“…Sample A was taking to complete failure at a strain of ~0.022. This failure strain agrees with the value reported by Baral et al for another M55J composite to within the error bars [Baral 2008]. …”

Artificial Muscles Based on Polypyrrole/Carbon Nanotube Laminates

“…Neat CNT sheets allow composite materials to be formed using methods analogous to those used for conventional fiber composites 9. For example, CNT sheets can be layered as a fabric and then resin applied and the process repeated in a manner similar to the hand lay‐up method.…”