Effect of Sintering Temperature on Microstructure and Hardness of SiC and Fly Ash Reinforced Copper Matrix Composite

Copper based composites with SiC and Fly ash as reinforcement is prepared by powder metallurgy process. During processing of composites the compaction pressure is maintained as 400MPa for all combination of materials. The prepared green compacts were sintered on both 700℃ and 900℃ and the results microstructure and hardness obtained through Brinell harness test were compared.

Shear melting and recovery of crosslinkable cellulose nanocrystal–polymer gels

Cellulose nanocrystals (CNC) are naturally-derived nanostructures of growing importance for the production of composites having attractive mechanical properties, and improved sustainability. Polymer–CNC composite gels display a number of the distinctive features of colloidal glasses and their response to the flow conditions encountered during processing of composites can be tuned by chemical additives.

Integration of resin flow and stress development in process modelling of composites: Part I – Isotropic formulation

Process modelling of thermoset matrix composites is typically divided into two distinct and sequential steps: (i) flow-compaction analysis before gelation of the resin when it behaves in a fluid-like manner, and (ii) thermomechanical analysis after gelation when appreciable modulus and thereby stress development occurs. This two-part paper presents a novel approach to integrate the simulation of resin flow and stress development seamlessly during the processing of composites. Part I lays the theoretical foundation for the simpler case of isotropic materials while Part II extends the methodology to the case of transversely isotropic materials. The formulation is implemented in a 2D plane strain finite element code written in MATLAB. Relevant numerical examples are presented to demonstrate both aspects of flow-compaction and stress development throughout the curing process of thermoset matrix composite materials. The effects of resin flow on the development and the final values of residual stresses are investigated.

Review of natural fibre-reinforced hybrid composites

Natural fibre-reinforced hybrid composites which contain one or more types of natural reinforcement are gaining increasing research interest. This paper presents a review of natural fibre-reinforced hybrid composites. Both thermoplastic and thermoset composites reinforced by hybrid/synthetic fibres or hybrid/hybrid fibres are reviewed. The properties of natural fibres, the properties and processing of composites are summarised.

Formulation and Manufacturing of Polybenzoxazine Composites

Polybenzoxazines offer excellent properties regarding mechanical performance, chemical stability, good flame resistance and low water absorption. High curing temperatures of benzoxazine monomers, however, impede the processing of composites. Therefore, this contribution presents a formulation of polybenzoxazines with the aim to reduce the curing temperature and facilitate Out of Autoclave (OoA) oven processes. This is accomplished by copolymerizing benzoxazine monomers with a poly(ε-caprolactone) based plasticizer yielding a resin exhibiting viscosities and reduced curing temperatures suitable for a vacuum infusion as well as compression process. Air void free composites were manufactured successfully featuring temperature dependent mechanical behavior.