Materials Science and Engineering: Properties, Polymers, Metallurgy, Timber, and Material Testing

Comprehensive vocabulary flashcards covering engineering materials, mechanical and chemical properties, polymers, forming techniques, metals, timber treatment, composites, and material testing methods.

Strength

The ability of a material to withstand forces of tension, compression, and shear.

Tension

The force of being pulled apart.

Compression

The force of being squashed.

Shear

The cutting, slicing, or tearing force.

Brittleness

The ability of a material to shatter or break easily on impact.

Hardness

The ability of a material to withstand indentation, scratching, and wear.

Toughness

The ability to withstand impacts and blows; the direct opposite of brittleness.

Elasticity

The ability of a material to return to its original shape when freed from the distorting force.

Plasticity

The ability of a material to stay in a new shape when freed from the distorting force.

Ductility

The ability of a material to be drawn or pulled into wire.

Malleability

The ability of a material to be drawn or pulled into a sheet.

Electrical Conductivity

The ability to allow electricity to flow through a material.

Thermal Conductivity

The ability of a material to allow temperature (heat) to pass through it.

Thermal Expansion and Contraction

The ability of a material to expand while heated and contract when cooled.

Resistivity

The opposite of electrical conductivity; the ability of a material to resist the flow of electricity.

Thermoplastics (Plastics/Polymers)

Polymers formed by addition polymerization with linear or branched chains that can be heated endlessly and bent into shape, having a low melting point, low tensile strength, and flexibility.

Thermosetting Plastics

Polymers formed by condensation polymerization with a 3D cross-linked chain structure that undergo a chemical change when heated the first time and cannot be reformed, exhibiting high melting point, high tensile strength, and stiffness.

Monomer

A single molecule that bonds together with other single monomers to create a polymer (e.g., plastic).

Injection Moulding

The most common plastic forming process where granules in a hopper are pushed and melted by a turning screw into a liquid, injected into a mould, cooled, and removed.

Blow Moulding

A forming process where soft heated plastic is enclosed in a mould and inflated with air to take the mould's shape; extensively used for plastic bottles, buckets, and barrels.

Extrusion Moulding

A continuous forming process used for bars and pipes where pellets are melted in a heated barrel and forced under high pressure through a custom-shaped die before cooling and cutting.

Vacuum Forming

A process where a heated, soft polymer sheet (such as LDPE) is pulled over a mould by vacuum suction; commonly used for food trays, blister packaging, and hollow children's toys.

Ferrous Metals

Metals that contain iron; they are magnetic and are the only metals capable of rusting.

Non-Ferrous Metals

Metals that do not contain iron; they are non-magnetic, do not rust, but can corrode.

Alloy

A mixture of two or more metals combined to improve strength, ductility, aesthetic appearance, or hardness.

Steel

An alloy formed from a combination of iron and carbon.

Solder

An alloy formed from a combination of lead and tin.

Brass

An alloy formed from copper and zinc.

Bronze

An alloy formed from a mixture of copper and tin.

Galvanizing

Coating a metal with a protective surface layer of zinc.

Electroplating

Covering a metal with a thin layer of another metal using an electric current, where the sacrificial anode is consumed to coat the cathode.

Anodizing

A process that uses electricity to artificially increase aluminium's naturally protective oxide layer.

Electrochemical Corrosion

Corrosion that occurs when two different metals come into contact in the presence of an electrolyte (e.g., water), causing the metal higher on the galvanic table to corrode.

Creosote (Cressode)

A dark-colored, oil-based pesticide liquid applied externally to protect timber; restricted to outdoor use.

Tantalizing

A pressure-treatment method that immerses timber in an oil-based pesticide bath, turning the wood a characteristic green color.

Glu-Laminate (Glulam)

Structural material made of timber layers bonded with durable moisture-resistant adhesive and coated in moisture-resistant plastic, which can be formed around shaped moulds.

Ceramics

Compounds of metallic and non-metallic elements that are heated to become extremely hard and brittle.

Composites

Structural units created by combining two or more distinct materials (e.g., carbon fiber, cardboard, and reinforced concrete).

Smart Material

A material designed to provide a useful, reversible response to external stimuli or influences.

Phosphorescent Sheet

A smart material sheet that absorbs light energy and re-emits it for up to eight hours; used in emergency power-cut lighting.

Thermocolor Sheet

A self-adhesive smart material sheet that changes color in response to temperature variations.

Destructive Testing

Testing procedures that require the complete breakage or significant permanent damage of the test piece.

Non-Destructive Testing

Material testing methods that produce zero damage to the test specimen.

Brinell Hardness Test

A laboratory hardness test utilizing a spherical ball-shaped indenter, typically intended for softer materials.

Vickers Hardness Test

A laboratory hardness test utilizing a sharp-angled indenter designed for evaluating extremely hard materials.

Izod Toughness Test

A laboratory impact test for less tough or brittle materials where a notched test piece is mounted vertically with the notch facing toward the striker/pendulum.

Charpy (Sharpie) Toughness Test

A laboratory impact test for tougher materials where the notched specimen is held horizontally with the notch facing away from the striker/pendulum.

Extensiometer

A specialized laboratory machine used to execute tensile strength testing on standardized specimens.

Tensile Strength Formula

$\text{Tensile Strength} = \frac{\text{Max Load}}{\text{CSA}}$, where $\text{CSA} = \pi r^2$.

Elastic Limit (Point D)

The threshold point on a tensile graph beyond which the specimen experiences permanent deformation rather than returning to its initial shape.

Max Load (Point E)

The peak force coordinate on a tensile graph marking the stage where the material begins to fracture.

Break Point (Point F)

The termination point on a tensile test curve marking the ultimate mechanical rupture and complete failure of the specimen.