DTE - Physical and working properties 1

physical properties

the characteristics of a substance that can be observed or measured in its natural state

Physical properties examples

-Absorbency

-Density

-Electrical conductivity

-Fusibility

-Thermal conductivity

Absorbency

The ability of a material to soak up or draw in heat, light or moisture.

Desity

mass per unit volume of a material

Electrical conductivity

The measure at which a material can transport electricity

Fusibility

The ability of a material to change into a liquid or molten state when heated to its melting point

Thermal conductivity

the ability of a material to transfer heat

working properties

how a material behaves when being worked or shaped

Working properties examples

Strength, hardness, toughness, malleability, ductility, elasticity

Elasticity

ability to return to its original shape after stretching or compression

Ductility

the ability of a substance to be drawn, pulled, or stretched without breaking

Hardness

The ability to withstand impact, wear, abrasion and indentation

Malleability

the ability to be bent, flattened, hammered, or shaped without breaking

Strength

The ability to withstand forces such as pressure, compression, tension or shear without breaking

Toughness

The ability to absorb shock without fracturing

Properties of layout paper

-Medium opacity

-smooth finish

-60-90 gsm

uses of layout paper

sketch and design work

Paper measurements

grams per square metre (GSM)

Properties of tracing paper

-low opacity

-off white

-60-90 gsm

Uses of tracing paper

copying, overlays and tracing drawings

Properties of cartridge paper

-thick

-Off white

-textured surface

-120-150sm

Uses of cartridge paper

Sketching, rendering in pencil, ink and pastel. Can be used for printing

Properties of corrugated card

Usually with carton board outer layers and a corrugated middle layer, giving the material the ability to provide protection against impact.

Uses of corrugated card

Protective packaging, model making, prototyping ideas, food packaging such as takeaway boxes

Properties of duplex card

Made up of two layers of paper, with the exterior often coated to make it more water-resistant and to give it a glossy sheen and waxy feel.

Uses of duplex card

food packaging

Properties of ink jet card

Treated card with a smooth finish and a bleed proof printable surface

Uses of ink jet card

Printing photographs and artworks

Hardwood

Sourced from deciduous trees

deciduous trees

trees that lose their leaves in the fall

Properties of hardwoods

- usually harder and stronger,

-slow growing

- close grain structure,

- sanded to a finer, smoother finish,

- can be given a higher-quality finish,

-more attractive grain pattern

-expensive

Hardwood examples

Oak, ash, mahogany, teak, birch, beech

Properties of ash wood

flexible, tough, and shock resistant. pale brown

Uses of ash wood

sports equipment and tool handles

Properties of beech wood

Fine finish, tough, durable and beige colour

Uses of beech wood

Children's toys and models, furniture and venners

Properties of mahogany wood

easily worked, durable, reddish brown

Uses of mahogany wood

High-end furniture and joinery, veneers

Properties of balsa wood

Very soft and spongy, with a good strength-to-weight ratio. pale cream/white

Uses of balsa wood

prototyping and modelling

Properties of oak wood

Tough, hard, and durable, high-quality Finnish. light brown

Uses of oak wood

Furniture, flooring, boat building, cladding, interior and exterior joinery

Softwood

Wood of coniferous (evergreen trees), often used in buildings or for making furniture

Properties of softwoods

-Flexible

-lightweight

-less dense

-cheaper

-fast growth time

-readily available

Examples of softwoods

Pine, Redwood, Cedar, Cypress, Fir and Spruce

Properties of pine wood

lightweight, easy to work with, pale yellowish brown

Uses of pine wood

Interior construction, furniture

Properties of spruce wood

Easy to work with, high stiffness to weight ratio, creamy white

Uses of spruce wood

Construction, furniture and musical instruments

Properties of larch wood

Durable, tough, good water resistance, good surface finish, pale reddish brown

Uses of larch wood

exterior cladding, decking, flooring, machined mouldings, furniture and joinery. venners

Chipboard

Wood chips that are glued together to make flat sheets. Often used in the floor construction of mobile homes

Plywood

Thin sheets of wood glued together so that the grains are at right angles to one another (an odd number of sheets will be used so that the grain on the front and back will always run the same direction.)

Medium-density fibreboard

tiny particles of timber are glued together and then compressed with a resin adhesive to produce large, dense, solid boards (furniture, kitchen units)

Properties of chipboard

- good compressive strength

- edges chip easily

-not water resistant unless treated

Uses of chipboard

Flooring, low-end furniture, kitchen units and worktops

Properties of plywood

-stable in all directions due to the alternate layering

-strong

-easy to machine

-Easy to cut and finish

Uses of plywood

Structural work, toys, desktops, indoor furniture, floorboards, shelving

Properties of MDF

-Smooth and easy to finish surface

-rigid and stable

-very absorbent

-not good in high humidity or damp areas

Uses of MDF

Flat pack furniture, toys, kitchen units and internal construction

Properties of chipwood

good compressive strength

Ferrous metals

metals containing iron

Veneers

Thin layers of wood glued to cheaper materials to make them. Ore aesthetically pleasing.

tensile strength

ability to resist breaking when pulled

malleable metals

Metals that can be shaped without breaking.

Alloys

mixtures of two or more metals

Advantages of alloys

cost effective, easy to use, has longevity, least technique sensitive, strong

Properties of ferrous metal

-most are magnetic

-vulnerable to rust without a protective finish

Properties of low-carbon steel

-tough

-ductile

-malleable

-rusts easily

Uses of low-carbon steel

Car bodies, steel building frames, piplines

Properties of cast iron

-Hard

-brittle

-self-lubricating

-magnetic

-resists deformation and rust

Uses of cast iron

-Kitchen pots and pans

-machine bases and bodies

-vices

-manhole covers

-post boxes

Properties of high-carbon steel

-Strong

-brittle

-hardwearing

-resists abrasion

-retains it shape

Uses of high-carbon steel

Tools, blades, scissors

Properties of non-ferrous metals

Lightweight, good conductivity, non-magnetic, ductile, malleable and resistant to corrosion

Uses of non-ferrous metals

electronics, guttering, pipes and road signs

Properties of aluminium

-Corrosion resistant

-lightweight

-ductile

-malleable

-good conductivity

-low density

Uses of aluminium

bike frames, drink cans, takeaway trays

Properties of zinc

-Low melting point

-high corrosion resistance

-brittle

-malleable

Uses of zinc

Galvanizing steel and making brass

Properties of copper

-Ductile

-malleable

-good conductivity

-unreactive

Uses of copper

Electrical wiring and plumbing

Properties of tin

-soft

-ductile

-malleable

-high corrosion resistance

-good electrical conductor

Uses of tin

soft solder, coatings for food cans

What is an alloy

A mixture of two or more metals

What is high-speed steel

a type of tool steel known for its high hardness, wear resistance, and heat resistance, making it suitable for high-speed cutting applications

Properties of high-speed steel

-Hard

-tough

-high level of resistance to frictional heat

Uses of high-speed steel

Cutting tools such as drill bits, mill cutters, taps and dies

Properties of stainless steel

-hard

-tough

-excellent corrosion resistance

Uses of stainless steel

Sinks, kitchenware, cutlery, and medical equipment

What is stainless steel

Steels containing chromium and nickel that are hard and resistant to corrosion

What is brass

An alloy of copper and zinc.

Properties of brass

-good resistance to corrosion

-easily cast

-malleable

-good conductor of heat and electricity

Uses of brass

musical instruments, plumbing fitments and ornate artefacts