Titanium and its alloys have several desirable properties including high strength to weight ratio, corrosion resistance, and biocompatibility. Common titanium alloys contain aluminum and vanadium. Titanium is used widely in aerospace applications due to its high strength and low density, as well as in medical implants and devices where it is compatible with the human body. However, titanium is expensive to produce due to its high reactivity at high temperatures requiring specialized production techniques.
Coefficient of Thermal Expansion and their Importance.pptx
Non ferrous ti ni
1. Titanium and Its Alloys
Medium density 4.54 Mg/m3 (steel 7.9 Mg/m3)
High melting point (1668°C) But relatively strong. σYS ≈
800 MPa (max ≈ 1100 MPa)
Stiffer than Aluminium; 107 - 116 GPa vs 70 GPa but not
as stiff as steel(207 GPa).
Highly ductile
Good corrosion resistance
Good strength to weight ratio
Expensive production due to reactivity at high
temperature.
Titanium and Its Alloys
Almost all Ti alloys contain aluminum
-Al increases ductility, and
-Reduces density
3. Titanium and its alloys are relatively new engineering materials that
possess an extraordinary combination of properties.
The pure metal has a relatively low density (4.5 g/cm3), a high melting
point [1668C], and an elastic modulus of 107 GPa ( psi).
Titanium alloys are extremely strong; room temperature
tensile strengths as high as 1400 MPa (200,000 psi) are attainable,
yielding remarkable specific strengths.
Furthermore, the alloys are highly ductile and easily forged
and machined.
4. The major limitation of titanium is its chemical reactivity with other
materials at elevated temperatures.
This property has necessitated the development of nonconventional
refining, melting, and casting techniques; consequently, titanium
alloys are quite expensive.
In spite of this high temperature reactivity, the corrosion resistance
of titanium alloys at normal temperatures is unusually high; they
are virtually immune to air, marine, and a variety of industrial
environments
5. Ti
Atomic symbol : Ti
Atomic weight : 47.90
Electron configuration : [Ar] 4s
Atomic radius : 144.5
Melting point : 1668 C
Boiling point : 3287 C
Oxidation state : 4,3,2
6. Sources of Ti
Meteorites and sun
Igneous rocks and their
sediments
Minerals like
rutile,ilmenite,and sphene
Titanates and iron ore
Commercially produced by
reducing titanium tetra
chloride (TiCl4)with
magnesium(Mg)
Rutile
Ilmenite
7. Physical properties of Ti
Non ferrous metal
Light weight and corrosion resistance
Lustrous gray-white metal
Low density
Resistant to dil. Sulphuric acid and hydrochloric acid
and most of the organic acids,chlorine gases and
chlorine solutions
Has high refractive index and optical dispersion
higher than diamond
Malleable and ductile
8. Alloys Of Titanium
Alpha alloy
Alpha alloys are those alloys that typically
contain aluminium(Al),tin (Sn)
They also contain Zr,N,Va,and Si
They do not respond to heat treatment but
they are weldable and are used for cryogenic
application,airplane parts,chemical
equipments
9. Alloys Of Titanium
Alpha-Beta Alloys
They can be strengthened by heat
treatment and aging
Used in aircraft and aircraft turbine
parts ,chemical processing equipment,
marine hardware and prosthetic devices
10. Alloys Of Titanium
Beta alloy
They have good hardenability,cold formability
when they are aged
They are slightly more denser then other Ti
alloys
They are the least creep resistant alloys ,they
are weldable
They are used for heavier duty purpose
on aircraft
11. Uses of Ti
for some watch cases and bracelets
in aircraft and space craft
in surgery
in sports equipment, automotive parts
in clubhead and shaft design
to make the outer case of the pacemaker
in some jewellery
12. APPLICATION OF Ti ALLOYS
Medical Application
Light, strong and totally bio-compatible, titanium is one of few
materials that naturally match the requirements for implantation
in the human body.
Medical grade titanium alloys(Ti-6Al-7Nb,Ti-5Al-2.5Fe,Ti-13Nb-
13Zr ,etc) have a significantly higher strength to weight ratio
than competing stainless steels.
The natural selection of titanium for implantation is determined
by a combination of most favourable characteristics including
immunity to corrosion, bio-compatibility, strength, low modulus
and density and the capacity for joining with bone and other
tissue – osseointegration.
The lower modulus of titanium alloys compared to steel is a
positive factor in reducing bone resorbtion.
.
13. APPLICATION OF Ti ALLOYS
Medical Application
Dental Implants
A titanium 'root' is introduced into the jaw bone with time subsequently allowed
for osseointegration.
The superstructure of the tooth is then built onto the implant to give an effective
replacement.
Cast denture framework with a
new high-strength Ti-6Al-7Nb
alloy.
14. APPLICATION OF Ti ALLOYS
Medical Application
Bone and Joint Replacement
Internal and external bone-fracture fixation provides a
further major application for titanium as spinal fusion
devices, pins, bone-plates, screws, intramedullary nails,
and external fixators
Cardiovascular devices
Titanium is regularly used for pacemaker cases and
defibrillators, as the carrier structure for replacement
heart valves, and for intra-vascular stents
External Prostheses
Titanium is suitable for both temporary and long term
external fixations and devices as well as for orthotic
calipers and artificial limbs, both of which use titanium
extensively for its light weight, toughness and corrosion
resistance
.
Biological Ti
Implants
Pacemaker
15. APPLICATION OF Ti ALLOYS
Medical Application
Surgical Instruments
A wide range of surgical instruments are made in titanium. The metal's
lightness is a positive aid to reducing any fatigue of the surgeon..
Titanium instruments withstand repeat sterilisation without compromise to
edge or surface quality, corrosion resistance or strength.
Titanium is non magnetic, and there is therefore no threat of damage to
small and sensitive implanted electronic devices
16. APPLICATION OF Ti ALLOYS
Aerospace Application
Engine powers to weight ratios, airframe strength, aircraft speed and range
can be achieved.
Ti alloys capable of operating at temperatures from sub zero to 600ºC are
used in engines for discs, blades , shafts and casings from the front fan to the
last stage of high pressure compressor, plug and nozzle assemblies.
Alloys used Applications
Ti-6Al-2Sn-4Zr-2Mo Creep and oxidation resistant alloy
Ti-3Al-8V-6Cr-4Zr-4Mo(Beta C) B alloy with established spring application
Ti-10V-2Fe-3Al B forging alloy for landing gear
Ti-3Al-2.5V Medium strength alloy for hydraulic tubing
Ti-4Al-4Mo-2Sn Higher strength heat treatable airframe and
engine alloy.
Ti-15Mo-3Nb-3Ai-0.2Si Oxidation and corrosion resistant B sheet alloy
Ti-6Al-5Zr-0.5Mo-0.25Si Engine alloy for spares and replacements
17. APPLICATION OF Ti ALLOYS
Aerospace Application
The entry end of a modern aeroengine
is huge (compare against the size of
the truck). The fan blades are
therefore also very large.
Given the large size and the
associated momentum when the
engine is spinning, it is imperative that
the weight of these blades should be
as small as possible. They are
therefore made of Ti-6V-4Al
Aeroengine fan blade made out of
Ti-6V-4Al wt%, almost a meter in
height.
18. APPLICATION OF Ti ALLOYS
Automotive Application
Automotive applications of titanium follow logically from the high strength,
low density and, in select applications, low modulus of titanium alloys, and
their excellent resistance to corrosion and oxidation.
Suspension spring, steering gears, connecting rods
Wheels, drive shafts, bumper supports.
Beta alloys such as Beta-CTM, LCB® (Low Cost Beta), as a class offer
designers many options to select a final combination of properties for
specific application e.g. as valve or suspension springs.
Ti springs Ti fasteners
19. APPLICATION OF Ti ALLOYS
Other Application
In computer industry titanium is
promising substrate for harddisk drives.
TiN thin films are used for
Plumbing Fixtures
Eyeglass Frames
Blades, Slitters and Knives
Jewelry
Punches and Dies
Cutting Tools
Ti harddisk
TiN coated
instrument
20. Nickel Alloys
Nickel: FCC (tough and ductile)
Good high and low temperature strength,
high oxidation resistance
Highly resistant to corrosion especially
alkaline.
Highly desirable material, but extremely
expensive
21. Nickel alloys
Nickel is often coated or plated on some metals
that are susceptible to corrosion as a protective
measure.
Monel, (65 wt% Ni - 28 wt% Cu & Fe-
balance), has very high strength and is
extremely corrosion resistant; it is used in
pumps, valves, and other components that are
in contact with some acid and petroleum
solutions.
Chromium improves corrosion resistance and
mechanical properties at elevated temperature
Inconel series (Ni-Cr alloys)
22. Super alloys
High temperature performance (strength) are used for
• Gas turbines, steam turbines, reciprocating engines
• Hot working and casting tools and dies
• Aircraft & space vehicles
• Nuclear and chemical industries
There are
Iron based alloys:
- 32% to 67% Fe, 15% to 22% Cr and 9% to 38% Ni.
- common alloys: Incoloy series
Cobalt based alloys:
- 30% to 65% Co, 19% to 30% Cr and up to 35% Ni.
- they retain their strength at high temp. but not as strong as Ni-
base superalloys
Nickel based alloys:
- 38% to 76% Ni, up to 27% Cr and 20% Co.
- are the most common superalloys
- common alloys: Hastelloy, Inconel, Nimonic,
23. The super alloys have superlative combinations of properties. Most
are used in aircraft turbine components, which must withstand
exposure to severely oxidizing environments and high temperatures
for reasonable time periods.
Mechanical integrity under these conditions is critical; in this regard,
density is an important consideration because centrifugal stresses
are diminished in rotating members when the density
is reduced.
These materials are classified according to the predominant metal
in the alloy, which may be cobalt, nickel, or iron. Other alloying
elements include the refractory metals (Nb, Mo,W, Ta), chromium,
and titanium.
In addition to turbine applications, these alloys are utilized in nuclear
reactors and petrochemical equipment.