AER208: Aerospace Materials

Vocabulary flashcards for key concepts in aerospace materials, covering historical context, material properties, and applications.

Junkers F13

The Junkers F13 was the first all-metal commercial transport aircraft, made from duralumin.

Supermarine Spitfire

The Supermarine Spitfire, made from aluminium alloy, was the most influential British aircraft in World War II.

Airbus A310

First commercial airliner to have a primary structure fully constructed from composite materials

Boeing 787 Dreamliner

Indicates direction of aerospace materials, made almost exclusively from advanced composite materials

Composites and light alloys

Light materials used to minimize launch weight for satellites

Composite Material

A material consisting of two or more physically distinct and separable constituents, with properties superior to those of the constituents.

Composite Types

Types of composites: Particulate, short fibre, long fibre, and nanocomposites.

Fibre Types

Glass, carbon, Kevlar, and silicon carbide.

Matrix Types

Thermosetting and thermoplastic polymers, ceramic (silicon carbide, carbon), and metal.

Radome

Protects delicate radar equipment and must be radar transparent.

Fibres

Have higher strength than bulk materials due to smaller flaws.

Types of glass fibres

Types of glass fibres: E-glass dominates, S-glass and R-glass have better properties, fused silica/quartz fibres have the maximum service temperature

Types of carbon fibres

Types of carbon fibres: PAN and Pitch

Types of polymer fibers

Types of polymer fibers: They all have highly aligned chains, generally, highly aromatic backbone (with the exception of UHMWPE)

Silicon carbide fibres

Dominate the ceramic fibre market

Polymer

A material consisting of long chains, generally of carbon atoms

Polymer Families

Linear, branched, and thermosetting.

Cure

Turning a liquid resin into a solid polymer

To Achieve in composite processing

To surround the fibres with a uniform coating of resin, to maximise the volume fraction of fibres, to maintain a uniform distribution of fibres and to minimise the number of voids

Injection moulding

Allows for the rapid production of complex shapes

wet lay-up

Low to moderate performance, high volume, high speed, and widespread and easy to do

Resin transfer moulding (RTM)

A processing technique: medium to high performance, partially automated process, and highly repeatable

Processing technique reliant on the operator to build the mould correctly

Vacuum assisted resin transfer moulding (VARTM)

Medium to high performance automated process

Filament winding

Low to high performance automated process that can produce long continuous sections

Pultrusion

A material consisting of fibres, either woven or unidirectional, resin in a β-stage precisely combined to control volume fraction, fibre orientation and layer thickness

Pre-preg

The automated tape placement process:

A process using the hand lay-up procedure using a robot manipulator in place of the human hand to lay pre-preg tape to make larger parts

Resin film infusion

Making a layer in the β-stage to combine with fibre mats heated under pressure to flow through the fibres and form the composite a pre-form

Preform

A package of fibres that make us a significant part of reinforcements of the composite that makes production of pats more uniform saving the operator handling individual layers

Preform types

Types of Preform: Woven fabrics, non-crimp fabrics, sewing, braiding and knitting

Vacuum bagging

Allows 1 atm of pressure to be applied to the surface to help removal of voids, consolidates the part

Autoclave cure

A pressure vessel that can also be heated and vacuum bagged to help with void removal to gives the highest composite performance of any current production technique

Microwave cure

Heats the volume, not the surface but hard to control the uniformity of heating

Hot pressing of composites

Provides both heat and pressure and Significant amounts of pressure must be applied so large, expensive, presses are generally required

Ceramic

An inorganic, non- metallic material, the common type being clay, but natural occurring crystals such a diamond and other gems would class as ceramics

Ceramics

High temperatures and difficult to process

Pyrolytic graphite

Is similar to natural graphite, but is imperfect there is some bonding between the platelets

Increasingly important in aerospace engineering; engines, rocketry, re-entry vehicles

Ceramic matrix composites

Ceramics for composites

Are often high temperature materials but brittle. Combining with fibres overcomes some of that disadvantage

Ceramics for composites can be produced in a number of ways

Techniques Used: Sintering of a slurry, Chemical vapour infiltration, Polymer infusion and pyrolysis, Reactive melt infiltration

Carbon-carbon, carbon-ceramic and ceramic- ceramic composites

Can be used to make very high temperature parts where microstructure control is critical

Oxide-oxide ceramics

Have an advantage over carbon-fibre based systems because they can’t oxidise in high temperature oxygen containing atmospheres are stable to high temperatures in applications such as engines