Valorization of lignin in polymer and composite systems for advanced engineering applications – A review

Current advancement on the isolation, characterization and application of lignin.

Advances, limitations and prospects of nondestructive testing and evaluation of thick composites and sandwich structures: A state-of-the-art review

This article presents the mechanical characterization of an eco composite consisting of a thermoplastic matrix reinforced by flax fibres. Different configurations of specimens were tested with uniaxial tensile loading and their mechanical behaviours were discussed. Moreover, the acoustic emission technique was used to detect the appearance of damage mechanisms and to follow their evolution. In addition, a list of these mechanisms was established by means of macroscopic and microscopic observations. The acoustic emission records were post processed by the k-means unsupervised pattern recognition algorithm. Depending on the specimen configuration, three or four classes of events were obtained. The acoustic characteristics of these classes were compared. Then, a correlation between these AE events classes and the damage mechanisms observed was proposed. Their effects on the mechanical behaviour of the material were investigated by means of a variable called the Sentry Function.

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Mechanical behaviour and damage mechanisms analysis of a flax-fibre reinforced composite by acoustic emission

Effects of lubrication on gear performance: A review

Life and damage mode modeling applied to plastic gears

Development of novel green and biocomposite materials: Tensile and flexural properties and damage analysis using acoustic emission

Mechanical properties and drop-weight impact performance of injection-molded HDPE/birch fiber composites

This study reports the effects of wood fibers and 3 wt% maleic anhydride-grafted polypropylene used as coupling agent on the tensile properties of polypropylene/wood composites. Compounding was don...

Formulation and tensile characterization of wood–plastic composites: Polypropylene reinforced by birch and aspen fibers for gear applications

A biocomposite was prepared using paper industry wood fibers (birch) mixed with a thermoplastic matrix of linear low-density polyethylene (LLDPE) at various fiber weights. Monotonic and load-unload tensile tests were performed at room temperature. The acoustic emission (AE) technique was used to characterize microstructural damage events leading to overall failure of the biocomposite. The behavior evolution (stress/strain) of the biocomposite appears to be correlated with the evolution of the AE cumulative energy, exhibiting four phases. The failure mechanisms in the short fiber-reinforced thermoplastic composites were identified using a neural network based on a Kohonen non-supervised self-organizing map (KSOM). Three parameters of the AE burst signals (amplitude, count and duration) were found to be very useful in classifying damage modes. As a result, a new damage mode definition is proposed based on a neural network with three parameters. The participation of each mode in the final failure was evaluated. The results indicated that fiber content plays a primary role in biocomposite failure. This finding has been further supported by scanning electron microscopy (SEM) micrographs of the fractured face.

Demagna Koffi

Papers

Life and damage mode modeling applied to plastic gears

Development of novel green and biocomposite materials: Tensile and flexural properties and damage analysis using acoustic emission

Mechanical properties and drop-weight impact performance of injection-molded HDPE/birch fiber composites

Formulation and tensile characterization of wood–plastic composites: Polypropylene reinforced by birch and aspen fibers for gear applications

Characterization of Tensile Damage for a Short Birch Fiber-reinforced Polyethylene Composite with Acoustic Emission