The working properties, stock forms and sizes, common uses and environmental impact of the following: 

– foam core/foam board 

– foil backed and laminated card, e.g. Tetra Pak® 

– manufactured boards ○ chipboard ○ engineered wood ○ medium density fibreboard (MDF) ○ plywood ○ blockboard 

– fibre reinforced materials ○ glass fibre reinforced plastic (GRP) ○ carbon fibre reinforced plastic (CFRP). 

A composite material is a material that combines two or more materials with different properties

By the end of this unit you should have developed a knowledge and

understanding of:

• the specific names and classifications of composites

• what constitutes a composite material

• the performance characteristics of different types of composites

• why different types of composites are suitable for different applications

• common composite based products

• the benefits of using composite materials

Composites can be put in three main categories.

The term ‘man-made board’ is sometimes used to describe manufactured boards such as MDF and Chipboard where wood has been combined with resin to form a ‘new’ material - These type of boards have increased stability and resistance to warping etc. and have equal strength in all directions unlike natural timber.

These have been covered in the Woods section as they are generally considered manufactured boards.

Positives:

• Lightweight: Easy to handle and transport.

• Easy to cut: Can be cut with a utility knife or specialized foam board cutter.

• Smooth surface: Provides a good surface for mounting prints, photos, and other materials.

• Affordable: Generally inexpensive compared to other mounting options.

Negatives:

• Denting and crushing: The foam core can be easily dented or crushed, especially with rough handling.

• Warping: Can warp or bend over time, especially in humid environments.

• Not archival: Standard foam core is acidic and can damage artwork over time.

Typical Uses:

• Mounting: Photos, posters, artwork, and other flat materials.

• Signage: Creating signs, displays, and promotional materials.

• Model making: Architectural models, dioramas, and prototypes.

• Craft projects: DIY projects, school projects, and arts and crafts.

Environmental Impact:

Foam core is typically made from polystyrene, a type of plastic that is slow to degrade and can contribute to environmental pollution. While some manufacturers are starting to use recycled materials in their foam core production, it is still important to dispose of foam core responsibly. Some recycling facilities may accept foam core, but it is best to check with your local waste management provider for specific guidelines.

Positives:

• Durability: The multiple layers provide strength and resistance to tearing and punctures.

• Protection: The foil layer acts as an excellent barrier against oxygen, moisture, and light, preserving the contents and extending shelf life.

• Lightweight: The material is relatively light, making it easy to transport and handle.

• Printable: The paperboard layer provides a good surface for printing, allowing for attractive branding and labeling.

Negatives:

• Recyclability: Separating the different layers for recycling can be challenging, leading to lower recycling rates compared to other materials.

• Environmental impact: The production of aluminum foil is energy-intensive and can contribute to environmental concerns.

Examples of use:

• Food packaging: Milk cartons, juice boxes, and other liquid containers.

• Pharmaceutical packaging: Blister packs for medications.

• Cosmetic packaging: Sachets for creams and lotions.

Environmental impact:

While foil-backed and laminated card offers excellent protection and convenience, its environmental impact is a concern. The difficulty in recycling and the energy-intensive production of aluminum contribute to its environmental footprint. However, advancements in recycling technology and the use of recycled materials are helping to mitigate these concerns.

Summary

• composites are a mixture of materials combined to improve their properties.

• manufactured boards such as Plywood and MDF are composites because they are a combination of wood and resin.

• composites generally fall into one of three groups; fibre based composites, particle based composites and sheet based composites.

• fibre based composites include Carbon Fibre, GRP (glass reinforced plastic) and GRC (glass fibre reinforced concrete)

• particle based composites include concrete and cermet

• sheet based composites include manufactured boards.

• composites are now being used to replace traditional materials such as timber and metal.