A proposal for similitude in characterizing fatigue delamination behavior with fibre bridging of carbon-fibre reinforced polymer composites

Methods based on fracture mechanics have been widely used in fatigue delamination growth (FDG) characterization of composite laminates. These methods are based on the similitude hypothesis. It is therefore important to have appropriate parameters to well represent the similitude, which is useful for fatigue delamination test standard...

Hygrothermal effects on fatigue delamination behavior in composite laminates

Fatigue delamination growth (FDG) is an important failure in composite structures during their long-term operations. Hygrothermal aging can have significant effects on interlaminar resistance. It is therefore really necessary to explore FDG behavior in composite laminates with hygrothermal aging. Dynamic mechanical thermal analysis (DMTA),...

Fractographic analysis of damage mechanisms dominated by delamination in composite laminates: A comprehensive review

Polymer composite laminates have established themselves as essential materials across a wide type of industrial fields because of their specific mechanical properties such as high strength and low weight. Among the main issues they face is susceptibility to delamination damage. This comprehensive review paper investigates various damage...

Shearography non-destructive testing and defect characterisation of thick composite structures

THICK composite materials, e.g., thickness of more than 50 mm, are increasingly being used across diverse industry sectors owing to their significant advantages of weightsavings, superiormaterial properties and load-carrying capability. These materials tend to be adopted in safety-critical applications such as large primary or secondary load...

Delamination Initiation and Propagation in Composite Laminates

Fibre-reinforced polymer composite laminates are used extensively nowadays in various applications due to their superior mechanical properties. However, a great weakness of composite laminates is their susceptibility to out-of-plane concentrated loading (which can be broadly divided into quasi-static indentation and impact) owing to their weak...

A numerical framework for simulating progressive failure in composite laminates under high-cycle fatigue loading

In this work, a recently proposed high-cycle fatigue cohesive zone model, which covers crack initiation and propagation with limited input parameters, is embedded in a robust and efficient numerical framework for simulating progressive failure in composite laminates under fatigue loading. The fatigue cohesive zone model is enhanced with an...

Fatigue delamination behavior in composite laminates at different stress ratios and temperatures

This study provides an investigation on mode I fatigue delamination growth (FDG) with fibre bridging at different R-ratios and temperatures in carbon-fibre reinforced polymer composites. FDG experiments were first conducted at different temperatures of R-ratios 0.1 and 0.5 via unidirectional double cantilever beam (DCB) specimens. A fatigue...

Analysis of Stochastic Matrix Crack Evolution in CFRP Cross-Ply Laminates under Fatigue Loading

The present work aims at understanding the stochastic matrix crack evolution in CFRP cross-ply laminates under tension–tension fatigue loading. An experimental campaign was carried out on twenty-three specimens at different stress levels, while two optical techniques were used for the in-situ monitoring of the accumulation of transverse...

Short-term Structural Performance of Self-monitoring Composite Marine Propellers

As a primary component of the marine propulsion systems, ship propellers have been traditionally made of nickel-aluminium-bronze (NAB) or manganese bronze (MB). With the development of fibre reinforced composite materials, the advanced plastic materials are considered to be applied in the manufacturing of marine propellers. Compared to...

A quantitative assessment of the damage mechanisms of CFRP laminates interleaved by PA66 electrospun nanofibers using acoustic emission

Interleaving composite laminates with nanofibrous mat is one of the most reliable methods for increasing interlaminar fracture toughness. The present study seeks to find out how the damage mechanisms of carbon fiber reinforced polymers (CFRPs), subjected to the mode-I and mode-II fracture tests, are affected while those are modified by...

Micromechanical validation of a mesomodel for plasticity in composites

In this paper, the performance of a recent homogenized orthotropic plasticity model for fiber reinforced composites (Vogler et al. (2013)) is investigated by comparing the model response against a micromechanical model. It is assumed that the micromechanical model which contains a recent plasticity model for polymers (Melro et al. (2013a,b))...