An instrumented indentation method is developed for generating maps of time-dependent viscoelastic and time-independent plastic properties of polymeric materials. The method is based on a pyramidal indentation model consisting of two quadratic viscoelastic Kelvin-like elements and a quadratic plastic element in series. Closed-form solutions for indentation displacement under constant load and c...

In this article, hybrid composite laminates with shape memory alloy (SMA) and glass fiber (GF) as the reinforced phase, and epoxy resin as the host material, were manufactured by vacuum-assisted resin injection (VARI) processing. The SMA wires were embedded into the GF/epoxy composites with three kinds of modes. The effect of SMA content and the position on the flexural, low-velocity impact per...

Three types of analyses are combined to investigate the effect of missing fibers in periodic continuous fiber composites that are subjected to thermomechanical loadings. The representative cell method is employed in the first analysis for the construction of Green’s functions elastic fields for the fiber–matrix interfacial jumps problem. As a result, the infinite domain problem is reduced, in c...

The fibers extracted from the piassava palm tree, scientifically known as Attalea funifera, are among the stiffest lignocellulosic fibers being considered for polymer composite reinforcement. Characterization of piassava composites have been carried out for different polymeric matrices and mechanical tests. In this work the tensile properties of DGEBA/TETA epoxy matrix composites reinforced wit...

Additive manufacturing technologies offer new ways to fabricate cellular materials with composite cell walls, mimicking the structure and mechanical properties of woods. However, materials limitations and a lack of design tools have confined the usefulness of 3D printed cellular materials. We develop new carbon fiber reinforced, epoxy inks for 3D printing which result in printed materials with ...

Carbon nanotubes (CNTs ) are considered to be one of the novel reinforcement for developing advanced nanocomposites due to their outstanding thermo-mechanical properties. Multi-walled carbon nanotubes (MWCNTs ) are developed by arc discharge method. To enhance the dispersion of CNTs in polymer matrix, CNTs are modified with chemical treatment and processed by ultrasonication process. Surface ch...

Intumescent coatings are commonly used as passive fire protection systems for steel structures. The purpose of this work is to explore whether these can also be used effectively on glass fibre-reinforced epoxy (GRE) composites, considering the flammability of the composites compared to non-flammable steel substrate. The thermal barrier and reaction-to-fire properties of three commercial intumes...

To improve the dispersion effectiveness of carbon nanotubes (CNTs) in epoxy and adhesion resulted composites on steel substrates, this paper proposed to surface treat CNTs using carboxymethyl cellulose (CMC) epoxy-CNTs composite. The characterizations properties reinforced by CMC treated were then systematically investigated. with three different weight fractions (0.5%, 1%, 2%) CMCs their compo...

Evolution of microdamage in advanced composites was experimentally studied in this paper. A new method of acoustic emission (AE) analysis of histories of different damage mechanisms was formulated based on a combination of transient AE classification and multiparameter filtering. The capabilities of the method were illustrated on examples of damage evolution in several graphite/epoxy composites...

The application of natural flax fibre/epoxy composites is growing in the automotive sector due to their good stiffness and damping properties. However, impact damage resistance flax/epoxy limited brittle nature both epoxy fibres strong fibre/matrix adhesion. Here, biobased thermoplastic cellulose acetate (CA) deployed as a fibre treatment alter development subjected low-velocity impact. perfora...