Simulation Supported Development of Lightweight Panels with High Delamination Resistance

Composite materials which are reinforced with 3D warp interlock fabrics have outstanding mechanical properties such as higher delamination resistance, ballistic damage resistance and impact damage tolerance by means of their improved structural properties. Textile reinforcements are exposed to large deformations in the production stage of composite materials which have complex shape. Although good formability properties of 3D warp interlock fabrics in forming process were already proven by recent studies, further information is needed to elucidate forming behaviours of multi-layer fabrics which is produced with high stiffness yarns like carbon. In this study, 3D warp interlock carbon fabrics were produced on a prototype weaving loom and the same carbon yarn was used in two fabric directions with equal number of yarn densities. Fabrics were differentiated with regard to the presence of stuffer warp yarn, weave pattern and parameters of binding warp yarn which are angle and depth. Therefore, the effect of fabric architecture on the mechanical and formability properties of 3D warp interlock carbon fabrics could be clarified. Three different breaking behaviours of fabrics were detected and they were correlated with crimp percentages of yarn groups. In addition, the bending and shear deformations were analysed in view of parameters of fabric architectures. Two distinct forming behaviours of fabrics were determined according to the distribution of deformation areas on fabrics. Moreover, the optimal structure was identified for forming process considering the fabric architecture.

Download Full-text

Piezoelectrically induced nonlinear resonances for dynamic morphing of lightweight panels

Journal of Sound and Vibration ◽

10.1016/j.jsv.2021.115951 ◽

2021 ◽

Vol 498 ◽

pp. 115951

Author(s):

Andrea Arena ◽

Walter Lacarbonara

Keyword(s):

Nonlinear Resonances ◽

Lightweight Panels

Download Full-text

Improving the delamination resistance and impact damage tolerance of carbon fibre-epoxy composites using multi-scale fibre toughening

Composites Part A Applied Science and Manufacturing ◽

10.1016/j.compositesa.2021.106624 ◽

2021 ◽

Vol 150 ◽

pp. 106624

Author(s):

Anil R. Ravindran ◽

Raj B. Ladani ◽

Anthony J. Kinloch ◽

Chun-Hui Wang ◽

Adrian P. Mouritz

Keyword(s):

Carbon Fibre ◽

Damage Tolerance ◽

Impact Damage ◽

Epoxy Composites ◽

Multi Scale ◽

Delamination Resistance

Download Full-text

Delamination Resistance of Two Hybrid Ceramic-Composite Laminates

Journal of the American Ceramic Society ◽

10.1111/j.1151-2916.1997.tb03229.x ◽

2005 ◽

Vol 80 (12) ◽

pp. 3029-3037 ◽

Cited By ~ 16

Author(s):

Willard A. Cutler ◽

Frank W. Zok ◽

Fred F. Lange ◽

Panos G. Charalambides

Keyword(s):

Composite Laminates ◽

Ceramic Composite ◽

Delamination Resistance ◽

Hybrid Ceramic ◽

Two Hybrid

Download Full-text

Delamination resistance of composite laminated structures reinforced with angled, threaded, and anchored Z-pins

Journal of Composite Materials ◽

10.1177/0021998318805201 ◽

2018 ◽

Vol 53 (11) ◽

pp. 1507-1519 ◽

Cited By ~ 5

Author(s):

Ananth Virakthi ◽

Soonwook Kwon ◽

Sung W Lee ◽

Mark E Robeson

Keyword(s):

Fracture Toughness ◽

Double Cantilever Beam ◽

Nonlinear Finite Element ◽

Mode I ◽

Finite Element Models ◽

Mechanical Interlocking ◽

Delamination Resistance ◽

Novel Approaches ◽

Laminated Structures ◽

Cohesive Zones

The delamination resistance of Z-pinned laminates is directly dependent on the strength of the pin–laminate bonding at the interface. In this paper, we investigate novel approaches to the Z-pinning technology in order to increase delamination strength via enhancing mechanical interlocking of the pins. Toward this end, we study the effect of pin insertion at an angle to the vertical in contrast to the conventional vertical pin insertion. Subsequently, a novel variety of pin, namely the threaded pin, is studied as a candidate for reinforcement which increases mechanical interlocking between the pin and the laminate as well as the epoxy-pin contact area, thus delaying delamination. In addition, the effect of anchoring reveals the length of smooth metal pins on to the surface of the laminate before curing on delamination strength is investigated. Experiments performed show increase in tensile pullout strengths when angled, threaded, or anchored pins are used. These experimental results for tensile pullout strengths validate nonlinear finite element models incorporating cohesive zones at the pin–laminate interface. In addition, fracture toughness and delamination resistance under mode-I loading are investigated by performing experiments on double cantilever beam specimens. Results demonstrate the superior delamination resistance properties for angled, threaded, and anchored pin inserts.

Download Full-text