Anti‐symmetrical curved composite laminate subject to delamination induced by thermal cycling

Abstract

Composite structures usually undergo to temperature variations in aircraft during landing/taking off and when cruising at high altitude. Under these conditions and in combination with curved structures, they can generate severe thermal stresses that induce delaminations. Considering the importance of studying delamination in these conditions, this research imposed an anti‐symmetrical laminate to cyclic temperature variations of 130 °C and −70 °C with the objective of inducing varied curvatures and, consequently, crack growth. Different from standardized test procedures, this test setup elastically deformed coupons without external forces and forward experimentally and numerically evaluated the strain energy release rate (SERR) during crack propagation. This procedure enabled the assessment of delamination rate (da/dN) as a function of maximum SERR. The experimental results were compared with numerical results obtained by ABAQUS Finite Element code. Despite large scatter in experimental results, a reasonable correlation between experimental and numerical results was obtained in terms of crack growth rate (da/dN) as a function of the maximum SERR.

Temperature effect on the static mode I delamination behavior of aerospace‐grade composite laminates: Experimental and numerical study

“…Delamination is regarded as one of the most life‐limiting failure modes for these materials 6–8 . Furthermore, aerospace composites may be exposed to diversified environmental conditions 9,10 . The temperature effect on the fracture behavior of adhesively bonded joints had been investigated by Khoramishad et al 11 It was showed that the presence of graphene oxide nanoplatelets in the adhesive layer changed the joint strength considerably differently depending on the testing temperature.…”

“…[6][7][8] Furthermore, aerospace composites may be exposed to diversified environmental conditions. 9,10 The temperature effect on the fracture behavior of adhesively bonded joints had been investigated by Khoramishad et al 11 It was showed that the presence of graphene oxide nanoplatelets in the adhesive layer changed the joint strength considerably differently depending on the testing temperature. The effect of multiwalled carbon nanotubes (MWCNTs) on the creep behavior of adhesively bonded joints was also studied.…”

Fatigue characterization study of CFRP under hygrothermal environment based on continuum damage mechanics model

“…Carbon fibre-reinforced polymers (CFRPs) are advanced materials used for highly loaded lightweight structures and are now attached with high importance to the aircraft industry, automotive, construction and other high-performance applications. 1,2 Through a lot of long-term studies, the advantages of high performance, low weight and designable properties of CFRP have been verified. The applications of CFRP have been proved to reduce the life-cycle cost in many cases.…”

Thermal cycling influences on compressive deformations of laminate composites

“…Zhang et al [17] evaluated the epoxy matrix composites exposure to thermal cycling between −55 and 120 C. It was found that the mass and volume changes of composites and resins after 160 cycles were <1.0%. Treml et al [18] investigated the crack growth of an anti-symmetrical laminate in condition of cyclic temperature variations of 130 and 70 C. There is no doubt that experimental methods in studying relations between thermal cycling and mechanical behaviors lay a solid foundation for the usage of composite structures. Although experimental procedure needs enormous costs.…”