Non Ferrous Materials Flashcards
What 3 lightweight materials are commonly used in aircraft?
Titanium
Aluminium
Magnesium
Name some advantages of titanium
High strength to weight ratio
Temperature resistant
Corrosion resistant
The strength of titanium is equal to steel but 56% of the weight of steel
Name the disadvantages of titanium
Easy to ignite
Hard to work with
What precautions must you take when cutting or grinding titanium?
Always have a fire extinguisher nearby
Use cutting fluid
Low cutting speed
Use sharp tools and always replace when worn
In what situations must titanium be protected from the atmosphere?
In high temperatures
At what temperatures will titanium ignite with the presence of oxygen?
1950F or 1065C
At what temperatures will titanium ignite with the presence of nitrogen?
1500F or 815C
How do you protect titanium from igniting with oxygen and nitrogen?
Heat up the titanium with argon and helium gas
What are some advantages of aluminium?
Corrosion resistant
High strength to weight ratio
What are some disadvantages to aluminium?
Flammable
Malleable
Hard to work with
What is a property of pure aluminium?
It is extremely malleable
How is aluminium identified?
Identified by 4 digits
What does the 4 digit system signify?
NOT COMPLETED
What is the process called to protect the surface of aluminium?
Cladding
What is cladding?
A thin layer of pure aluminium with 1% zinc on both sides as a means of corrosion protection
What does the ink print on a material correspond to?
The material grain structure
What is the thickness of the clad layer approximately equal to?
3-5% of the material thickness
What are examples of strain hardness materials?
Non-heat-treatable materials
1100 - pure aluminium
3003 - aluminium with the addition of manganese
5052 - aluminium with the addition of magnesium
What is the most common non-heat-treatable material?
5052 - aluminium with magnesium
What are some examples of heat-treatable aluminium alloys?
2011
2017
2024
7075 - aluminium zinc
What are the similarities and differences between 2011, 2017, and 2024?
They are all aluminium copper alloys but have different alloying elements
What is the most common heat-treatable aluminium alloy?
2024
What are the two types of heat treatment used for aluminium?
Annealing and solution heat treatment
Describe the process of annealing for aluminium
The aluminium alloys are heated to an elevated temperature and are soaked at this temperature for a length of time and are cooled slowly in still air or in a switched off furnace
Describe the process of solution heat treatment for aluminium alloys
The aluminium alloys are heated in a molten sodium or potassium nitrate bath or a hot-air furnace
What is rapid cooling needed after heat treatment and rapid cooling must happen within what?
Rapid cooling is necessary as it can cause inter granular corrosion
It must happen within 10 seconds of heat removal
How many methods are used to harden aluminium and what are they?
3 methods
Cold working
Natural age hardening
Artificial hardening
Describe the process of hardening in aluminium
When copper is forced to precipitate at grain boundaries and harden the aluminium alloys
What type of hardening for aluminium alloys is done at room temperature and takes a period of 7 days?
Natural age hardening
What type of hardening for aluminium alloys raises the temperature of the alloy between 1200 and 1900 degrees C so it increases precipitation and strength?
Artificial hardness
How many times can aluminium alloys be treated before scrapped?
Maximum of 3 times
What are the basic temper states and what they mean?
F - as fabricated
O - annealed
H - strain hardened (for non heat treatable)
W - solution heat treated
T - heat treated to produce stable tempers
Describe the heat treatment used and the type of hardening method for T3, T4 and T6 aluminium alloys
T3 - solution heat treated and cold worked
T4 - solution heat treated and naturally aged
T6 - solution heat treated and artificially hardened
What are some advantages of using magnesium?
It is lighter than aluminium
High strength to weight ratio
What are some disadvantages to magnesium alloys?
Easy to corrode
Difficult to work with
Highly flammable
What should you put a magnesium alloy out with if it ignites?
Dry powder or helium or argon fire extinguisher
Or a bucket of sand
NEVER WATER
What system identifies magnesium alloys?
ASTM system
What does ASTM stand for?
American Society for Testing Materials
What heat treatments can be used for magnesium alloys?
Same as aluminium
Annealing
Hardening
Solution heat treatment
What does GLARE stand for?
Glass Reinforced Laminate
How can glare be tailored to specific applications?
Through the alternating layers of fibres
What is the difference between annealing and solution heat treatment?
Solution heat treatment uses the process of quenching and annealing doesnt
What are some properties GLARE has?
Good fatigue resistance Damage tolerant Flame resistant High strength Good thermal insulation
