2.7 ~ Performance characteristics of composites

Define composite

: A material comprised of two or more different materials, resulting in a material with enhanced properties

Two commonly used composites: CFRP and GRP; lightweight, corrosion resistant, tough, hard, low thermal expansion. Can be easily moulded into 3D forms via the lay-up method

CFRP composition

Carbon fibres mixed with polyester resin

CFRP properties

Lightweight, Corrosion resistant, tough, hard, good compressive strength, low thermal expansion

CFRP uses

Sports equipment, bicycle frames, tennis rackets, fishing rods, racing car bodies and parts, helmets, prosthetics

GRP composition

Glass fibres mixed with polyester resin

GRP properties

Lightweight, corrosion resistant, tough, hard, low thermal expansion, good compressive strength

GRP uses

Boat hulls, pond liners, kayak shells, sports car bodies and parts, locomotive train cabs

Tungsten carbide composition

A cermet (mixture of ceramic and metal particles) Ceramic tungsten and cobalt metal

Tungsten carbide properties

Hard, tough, resistant to high temperatures, corrosion resistant

Tungsten carbide uses

Cutting tools such as drill bits, lathe tool tips, router bits, kitchen knives

Aluminium composite board composition

Aluminium sheets with a polyethene core

Aluminium composite board properties

Lightweight, rigid, tough, malleable, good thermal and sound insulation, good vibration damping

Aluminium composite board uses

Soundproofing panels in cars, buildings and boats; signage

Concrete composition

Cement powder, sand, aggregate particles mixed with water

Concrete properties

High compression strength, low tensile strength, few surface defects, easy to mould

Concrete uses

Pathways, beams, blocks, driveways, house foundations

Reinforced concrete composition

Cement powder, sand, aggregate particles and low carbon steel rods (rebar) mixed with water

Reinforced concrete properties

High compression and tensile strength; consistency across the structure; few surface defects; fire resistant

Reinforced concrete uses

Buildings, bridge piles and bridge spans, retaining walls, Grid floors

Fibre cement composition

Cement powder, sand, aggregate particles and polymer or steel fibres mixed with water

Fibre cement properties

Lighter in weight than reinforced concrete; hard; tough; good at low temperatures and in freeze/ thaw situationis

Fibre cement uses

Suspended floors, complex geometric shapes, pathways

Engineered wood (e.g. glulam - glued laminated timber) composition

Timber laminates and MF adhesive

Engineered wood properties

Good aesthetics; natural alternative to reinforced concrete; lighter than concrete alternatives; fire resistant,Good structural stability; corrosion-proof

Engineered wood uses

Beams, bridges, domes, arches, decking, roof beams, rafters