Fatigue Characterization of Functionalized Carbon Nanotube Reinforced Carbon Fiber Composites

Abstract

The primary purpose of this analytical report is to compare tension-tension fatiguing of a carbon fiber composite to tension-compression fatiguing. Although carbon fiber composites hold up well in tension-tension fatiguing, there is little knowledge of the effects of tension-compression cyclic testing, especially in the higher regimes. The composites were fabricated using the vacuum assisted resin transfer molding method, VARTM, and are composed of IM7 four harness satin weave carbon fiber (54% by volume) and Epon 862 with curing agent W (46% by volume). The current research shows that carbon fiber composites are resistant to tension-tension fatiguing. However, when the composite must also endure compressive forces the fatigue life is considerably shorter. The results show that at R-ratios, maximum stress over minimum stress, of 0.1 &-0.1 tension-compression fatiguing will result in a failure three times earlier then tension-tension fatiguing for the same maximum stress value. Microscopy shows the extreme damage that carbon fiber epoxy composites endure during tension-compression fatiguing. ________________________________________________________________________ 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU 18. NUMBER OF PAGES 5 19a. NAME OF RESPONSIBLE PERSON

Crack growth as a function of temperature variation in carbon fiber/epoxy

“…In woven carbon fiber reinforced polymers, CFRP, a number of damage modes occur before this final failure. Previous investigations have shown debonding of fiber-matrix interface, fiber breakage, normal and longitudinal matrix cracking under tensiontension and tension-compression loading (Wilkerson et al, 2007).…”

Thermal fatigue life of carbon nanotube wire and unidirectional carbon fiber/epoxy composite (UCFEC) in earth orbit

“…This material can be applied in many industries such as aerospace, turbine blades, etc. Other characteristics of these materials are high strength and lightweight (Wilkerson et al, 2007). Furthermore, carbon fibers may be applied in composites to manufacture the flaps, aileron, and landing gear doors (Voicu, 2012).…”