Introduction Material Merit and De-merit Raw Material Forming Processing

1. Material of Aircrafts
Presented by
M Faheem Ullah 19013123-019
Masab Tanveer 19013123-017
Iraza –ul-Hassan 19013123-027
Kazim Gujjar 19013123-023
Muhammad Hassan 19013123-029
1

2. Outlines
• Introduction
• Material
• Merit and De-merit
• Raw Material
• Forming
• Processing
2

3. 1903 - First Flight - The Wright Brothers
• Wood - natural composite - high strength to weight
ratio
• Easy to work
• Tough and flexible
• Moisture absorption
• Anisotropic
3

4. 1915 – First all Metal Junker J-1
• Steel
• Weight – sluggish
• Un-maneuverable in flight
4

5. 1917 - Junkers J-7
• Duralumin – Al, 4% Cu, Mg and Mn
• Al – 2024, 7075
• Subsonic aircraft
• US Navy – Alclad
Duralumin with pure aluminum coating
• Al-Li alloys
Airbus A350 - wings and fuselage
• Supersonic - elevated temperatures
• Aluminium – low heat resistance
Source: Micheal F. Ashby, Materials selection in mechanical design, 3rd edition, 2005
5

6. Titanium
• High strength
• 40% lighter than steel
• Good creep properties
SR-71 Blackbird - highest flying, fastest aircraft
(wings and fuselage – titanium)
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7. Composite
Fiberglass - Boeing 707 - 1950s – 2% of the structure
• Weight reduction
• High corrosion resistance
• Good fatigue strength
• Reducing operating costs - fuel
• Improved efficiency
Glass-Reinforced” Fiber Metal Laminate (FML)
• Good impact and fatigue strength
• Better corrosion resistance
• Better fire resistance
• Lower specific weight
7

8. 2009 – Boeing 787 Dreamliner
• Weight breakdown by material type:
50% composite (fuselage, wings, tail, doors and interior)
20% aluminum (wing and tail leading edges)
15% titanium (engines components)
10% steel (various locations)
5% other
• 80% composite by volume
• 20% more efficient than the 767
8

9. Merits
Some of the many advantages for using composite materials are:
• High strength to weight ratio
• Fiber-to-fiber transfer of stress allowed by chemical bonding
• Modulus 3.5 to 5 times that of steel or aluminum
• Longer life than metals
• Higher corrosion resistance
• Tensile strength 4 to 6 times that of steel or aluminum
• Greater design flexibility
• Bonded construction eliminates joints and fasteners
• Easily repairable
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10. De-Merits
The disadvantages of composites include:
• Inspection methods difficult to conduct, especially delamination
detection
• Lack of long term design database, relatively new technology methods
• Very expensive processing equipment
• Lack of standardized system of methodology
• Great variety of materials, processes, and techniques
• General lack of repair knowledge and expertise
• Products often toxic and hazardous
• Lack of standardized methodology for construction and repairs
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11. Raw Material
Raw materials used in the manufacture of aeroplanes.
• Aluminium
• Titanium
• Steel
• Copper
• Fiber
• Glass
• Leather

12. Aluminum
• Aluminum is ideal for aircraft manufacture because it's lightweight
and strong.
• Aluminum is roughly a third the weight of steel, allowing
an aircraft to carry more weight and or become more fuel
efficient.
• Furthermore, aluminum's high resistance to corrosion ensures the
safety of the aircraft and its passengers.

13. Titanium
• Due to their high tensile strength to density ratio, high corrosion
resistance,
• ability to withstand moderately high temperatures without
creeping,
• titanium alloys are used in aircraft, armor plating, naval ships,
spacecraft, and missiles.

14. Steel
• Steel alloys have a greater tensile strength, as well as a higher
elastic modulus.
• As a result, steel is used in the parts of aircraft for which strength
is very important, such as in the design of landing gears.
• It typically comprises around 11-13 percent of the
materials used in an aircraft.

15. Copper
• In aircraft, copper is used primarily in the electrical system for
• bus bars,
• bonding,
• lockwire.
• Beryllium copper is one of the most successful of all
the copper base alloys.

16. Fibers
• The use of carbon fiber for aircraft bodies allows them to be more
fuel-efficient,
• more aerodynamic,
• and to be built with fewer and lighter parts.
• All of these factors add up to reduced costs in both manufacturing
and operations

17. Glass
• Aircraft windows are made a form of plexiglass, such as Lexan
polycarbonate, or acrylic plastics.
• This material is lightweight, relatively strong, and you can see
clearly though it.
• The glass is layered, and the middle layer usually has a tiny hole
in it to get rid of condensation

18. Leather
• As frequent fliers can notice, aircraft seat designs differ by the
upholstery material.
• During the short-haul flights, an artificial leather is used.
However, during the long –haul routes, the fabric is chosen

19. TITANIUM ALLOYS
• Titanium alloys are made by adding elements such as aluminum,
vanadium, molybdenum, niobium, zirconium and many others to
produce alloys such as Ti-6Al-4V and Ti-24Nb-4Zr-8Sn and several
others
• TYPES:
Depending on their influence on the heat treating temperature
and the alloying elements, the alloys of titanium can be classified
into the following
three types:

20. The alpha (α) alloys
These alloys contain a large amount of
α-stabilizing alloying elements such as
aluminum, oxygen, nitrogen or
carbon. Aluminum is widely used as
the alpha stabilizer for most
commercial titanium alloys because it
is capable strengthening the alloy at
ambient and elevated temperatures
up to about 550°C. This capability
coupled with its low density makes
aluminum to have additional
advantage over other alloying
elements such as copper and
molybdenum. However, the amount of
aluminum that can be added is limited
because of the formation of a brittle
titanium-aluminum compound when
8% or more by weight aluminum is
added.
LIMITATIONS:
The limitation of the α alloys of
titanium is non-heat treatable but
these are generally very weldable.
alpha-beta (α-β) alloys
These alloys contain 4–6% of β-phase
stabilizer elements like
molybdenum,vanadium, tungsten,
tantalum, and silicon. The amount of
these elements increases the amount of
β-phase is the metal matrix.
Consequently, these alloys are heat
treatable, and are significantly
strengthened by precipitation
hardening. Solution treatment of these
alloys causes increase of β-phase
content mechanical strength while
ductility decreases. The most popular
example of the α-β titanium alloy is the
Ti-6Al-4V with 6 and 4% by weight
aluminum and vanadium, respectively.
This alloy of titanium is about half of all
titanium alloys produced. In these
alloys, the aluminum is added as α-
phase stabilizer and hardener due to its
solution strengthening effect. The
vanadium stabilizes the ductile β-phase,
providing hot workability
of the alloy.
beta (β) alloys
These alloys exhibit the body
centered cubic crystalline form.
The β stabilizing elements used
in these alloy are one or more
of the following: molybdenum,
vanadium, niobium, tantalum,
zirconium, manganese, iron,
chromium, cobalt, nickel, and
copper. Besides strengthening
the beta phase, these β
stabilizers lower the resistance
to deformation which tends to
improve alloy fabricability
during both hot and cold
working operations. In addition,
this β stabilizer to titanium
compositions also confers a heat
treatment capability which
permits significant
strengthening
during the heat treatment
process.

21. Method Of “Ti Alloys” Processing:
1. Conventional Methods:
• Powder Metallurgy
• Self-propagating High Temperature synthesis
2. Advanced Methods:
• Atomisation
• Gas Atomisation
• Plasama Atomisation

22. 1. Powder Metallurgy
• It is one of the widely applied powder metallurgy (PM) based method for
manufacturing titanium alloys. In this method, the feedstock titanium powder is
mixed thoroughly with alloying elements using a suitable powder blender,
followed by compaction of the mixture under high pressure, and finally
sintered. The sintering operation is carried out at high temperature and
pressure treatment process that causes the powder particles to bond to each
other with minor change to the particle shape, which also allows porosity
formation in the product when the temperature is well regulated.This method
can produce high performance and low cost titanium alloy parts. The titanium
alloy parts produced by powder metallurgy have several advantages such as
comparable mechanical properties, near-net-shape, low cost, full dense
material, minimal inner defect, nearly homogenous microstructure, good
particle-to-particle bonding, and low internal stress compared with those
titanium parts produced by other conventional processes

24. 2. Self-propagating high temperature synthesis
• It is another PM based process used to produce titanium alloys.
The steps in this process include: mixing of reagents, cold
compaction, and finally ignition to initiate a spontaneous self-
sustaining exothermic reaction to create the titanium alloy. these
processes tend to produce brittle products because of cracks and
oxides formed inside the materials. Further, the high costs and
poor workability associated with these processes restrict their
application in commercial production.

25. 3. Atomisation using gas
• the metal is usually melted using gas and the molten metal is
atomised using an inert gas jets. The resultant fine metal droplets
are then cooled down during their fall in the atomisation
tower.The metal powders obtained by gas-atomization offer a
perfectly spherical shape combined with a high cleanliness level.
However, even though gas atomisation is, generally, a mature
technology, its application need to be widened after addressing a
few issues worth noting such as considerable interactions between
droplets while they cool during flight in the cooling chamber,
causing the formation of satellite particles. Also, due to the
erosion of atomising nozzle by the liquid metal, the possibility for
contamination by ceramic particles is high. Usually, there may also
be argon gas entrapment in the powder that creates unwanted
voids.

26. GLASS FIBRE
• Ancient Egyptians use glass fibers for decorative items in the 16th
and 17th century.
• But the use of glass fibers as a reinforcing material is a new idea.
• Continuous glass fibers were first manufactured in substantial
quantities by Owens Corning Textile Products in the 1930’s for high
temperature electrical applications.

27. RAW MATERIAL FOR GLASS FIBRE:
• The major ingredients are silica sand, limestone, and soda ash.
Other ingredients may include calcined alumina, borax, feldspar,
nepheline syenite, magnesite, and kaolin clay, among others.
Silica sand is used as the glass former, and soda ash and limestone
help primarily to lower the melting temperature. Other
ingredients are used to improve certain properties, such as borax
for chemical resistance. Waste glass, also called cullet, is also
used as a raw material.

28. PROCESSING:
Glass melts are made by fusing (co-melting) silica with minerals,
which contain the oxides needed to form a given composition. The
molten mass is rapidly cooled to prevent crystallization and formed
into glass fibers by a process also known as fiberization.

29. FIBERIZATION
• STEP1(BATCH MIXING AND MELTING):
• The glass melting process begins with
theweighing and blending of selected raw
materials.In modern fiberglass plants, this
process is highly automated, with computerized
weighing units and enclosed material transport
systems.The individual components are weighed
and delivered to a blending station where the
batch ingredients are thoroughly mixed before
being transported to the furnace. Fiberglass
furnaces generally are divided into three distinct
sections:
• Batch is delivered into the furnace section for
melting at about 1400°C, removal of gaseous
inclusions, and homogenization. Then, the
molten glass flows into the refiner section,
where the temperature of the glass is lowered
to about 1260°C.The molten glass next goes to
the forehearth section located directly above
the fiberforming stations.

30. FIBERIZING AND SIZING
• The molten glass flows through a platinum rhodium alloy bushing
with a large number of holes or tips (400 to 8000, in typical
production). The bushing is heated electrically, and the heat is
controlled very precisely to maintain a constant glass viscosity.
Optimum fiber formation is achieved with melts having a viscosity
ranging from 0.4 to 0.5 P. The fibers are drawn down and cooled
rapidly asthey exit the bushing.

31. FIBERIZING AND SIZING
• A sizing is then applied to the surface of the fibers by passing
them over an applicator that continually rotates through the sizing
bath to maintain a thin film through which the glass filaments
pass. The components of the sizing impart strand integrity,
lubricity, resin compatibility, and adhesion properties to the final
product, thus tailoring the fiber properties to the specific end-use
requirements.

33. References
1. Micheal F. Ashby, Materials Selection In Mechanical Design, 3rd
Edition, 2005
2. Peter L. Jakab, Wood To Metal: The Structural Origins of The
Modern Airplane, Journal of Aircraft, Vol. 36, No. 6, November –
December 1999
3. Júlio C. O. Lopes, Material Selection For Aeronautical Structural
Application, Ciência & Tecnologia Dos Materiais, Vol. 20, 2008