copper, aluminium and titanium alloys and there uses

1. Prepared By
Nandlal Birle
Mechanical Engg. Dept.

2. 1. Brasses
2. Bronzes
3. Copper – nickel alloys

3. • α phase – FCC structure
• β phase – BCC structure (disordered)
• β’ phase – BCC structure (ordered)
• γ phase – complex structure (brittle)

4.  Zinc (Zn) is predominated alloying element for Brasses.
 Up to 35 % of zinc be weight is called α – solid solution.
 Above 35 % of zinc the β – crystal is begin to form and its
continue up to 59 % of zinc.
 Between 35% and 47% of zinc, a mixture of α and β-crystals
exists.
 Above 50 % of zinc the γ – crystal is begin to form and its
continue up to 79 % of zinc.
 51% and 59% zinc consist of mixtures of β and γ-crystals.

5. 1. α – brasses
1. Red α – brasses
2. Yellow α – brasses
2. α – β brasses
1. Muntz metal
2. Naval brass
3. Leaded brass
4. High tensile brass
3. Cast brasses
1. Cast red brass
2. Cast yellow brass

6. 1. α – brasses
1. Red α – brasses
2. Yellow α – brasses
 Is quite ductile and soft at room temperature due to this
they are excellent cold working alloys.
 They also have good corrosion resistance.

7. Red α – brasses
Name Cu & Zn %
respectively
Properties Uses
Gilding metal 95 & 5 Gold color Making coins, medals, jewellery base
for gold plating
Commercial
bronze
90 & 10 Cold and hot
working
properties
Costume jewellery, lipstick cases and
grill work
Red brass 85 & 15 Good
corrosion
resistance
Condenser and H.E. tubing, electrical
sockets
Low brass 80 & 20 - Musical instruments, flexible hoses

8. yellow α – brasses
Name Cu & Zn %
respectively
Properties Uses
Cartridge
brass
70 & 30 Good
strength and
ductility
Cartridge case, radiator cores, tanks,
flash light shells
Yellow brass 65 & 35 Good
strength and
ductility
Reflectors, fasteners and springs
Admiralty
brass
71 & 23 & 1
Sn
Good
strength and
corrosion
resi.
Condenser and H.E. tubing in steam
power plants

9. yellow α – brasses
 Aluminium brass
 The yellow α – brasses brass is corrosive in marine
environment is called dezincification.
 Dezincification involves dissolution of the alloy, and
deposition of porous non-adherent copper.
 This penetrates the cross section of the metal and leads
to leakage.
 2 % aluminum and small amount of As inhibit
dezincification.

10. yellow α – brasses
 Aluminium brass contains 76Al-22ZN-2Al-0.04As.
 It forms a self-healed tenacious film in contact of sea
water.
 It is widely used in marine applications.

11.  α – β brasses contains 34 – 46% Zinc.
 This alloy contains two phase α and β’. β’ phase is hard
and brittle at room temperature.
 β’ phase makes it hard due to this it has low capacity of
cold working.
 This is best shaped by hot working processes.

12.  Types
Name Cu & Zn %
respectively
Properties Uses
Muntz metal 60 & 40 Cant be rolled
or forged
Condenser tube, valve stems, brazing
rods.
Naval brass 60 & 39 & 1
Sn
Good salt
water
corrosion
resistance
Marine hardware, propeller shaft,
piston road and valve stems
Leaded brass Additional 1-
3% lead
Good
machinability
Machine stock and gears

13. 1. Cast red brass – 85 % Cu, 5% Sn , Pb and Zn.
1. It has fair strength and corrosive resistance.
2. Also got antifriction prosperities.
3. Used in pipe fitting, bearing and small gears.
2. Cast yellow brass – 60% Cu, 38% Zn, 1%Sn and 1% Pb.
1. Low cost
2. Used in hardware fitting.

14.  Term bronze was previously applied for a copper alloy, with tin
as major alloying element.
 The simplest bronze contains 88% Cu with 12% tin.
 Bronze is any copper alloy containing other then zinc or
nickel.
 Other alloying elements like phosphorous, lead, nickel etc. are
also added to obtain favorable properties.
 Other than tin, elements like aluminium, silicon or beryllium
are also alloyed with copper producing different bronzes.
 Zinc also may be present in these alloys in relatively smaller
amounts.

15.  Bronzes are softer and weaker than steel.
 Corrosion resistance, heat and electric conductivity are also better
than steel, while the cost is higher than steels.
 Compared to brasses, these are having lower coefficient of friction,
higher strength, toughness, corrosion resistance and also higher
cost.
 Bronze is having good castability and anti-friction or bearing
properties.
 Bronzes are widely used for different purposes like bearings,
springs, industrial castings, bells and statues.

16.  Tin Bronze:
 Sn present 1 % at room temperature and 13.5% at 798 ºC in α-solid
solution
 Gun metal:
 an alloy of copper (88%), tin (10%), and zinc (2%). Originally used chiefly
for making guns
 Aluminium bronze:
 contains 4 – 11% aluminum. It has finest color and also called imitation
gold)
 Silicon bronze:
 Beryllium bronze:
 contains up to 2.5% of beryllium. It has much higher tensile strength than
other bronzes.)

17.  Aluminium occupies the third place among commercially used
engineering materials.
 It has low density, low melting point and high electrical and thermal
conductivities.
 It has low strength and hardness, but high ductility and malleability.
 On exposure to atmosphere, it forms a strong film of aluminium oxide on
its surface, which prevents further oxidation and corrosion.
 It is employed for lightly loaded structures and for electrical cables and
similar items.
 Aluminium has good machinability, formability, workability and
castability.
 It is non-magnetic, non-toxic, easily available and less expensive.
 The main drawback is its low strength and hardness.

19.  Maximum solubility of copper in aluminium is 5.65% at
550OC and it reduces to 0.45% at 300OC.
 Alloys containing between 2.5 and 5% copper will respond
to heat treatment by age hardening.
 Due to the increased strength, aluminium alloys are widely
used in commercial applications.
 Two main groups of aluminium alloys are wrought alloys
and casting alloys.

20.  Wrought alloys : Al-Mn and Al-Mg alloys form homogenous
solid solutions and are characterized by comparatively
lower strength and high ductility. Other examples are avial
(Al-Mg-Si) and duralumin (Al-Cu-Mg).
 Casting alloys: The best known casting alloy is the silumin
alloys. Alloys of Al and Cu also are suitable for casting. Many
of the casting alloys are heat treatable.

21.  Duralumin: A typical composition is 94% Al, 4% Cu
and 0.5% each of Mg, Mn, Si and Fe.
 High tensile strength and electrical conductivity.
 Widely used for aeroplanes, surgical and orthopedic
equipments.
 Y-alloy: Composition of this alloy is 92.5% Al, 4% Cu,
2% Ni and 1.5% Mg.
 High strength and hardness even at high temperature such as
200oC.
 Used for cylinder heads and crank cases of engines.

22.  Magnelium: The major alloying elements in this alloy
are magnesium and copper with Ni, Sn, Fe, Mn and Si in
small amounts.
 Better tensile strength and machinability, but it is brittle.
 Used by aircraft and automobile industries.
 Silumin alloys: Alloys based on Al-Si system are known
as silumin alloys.
 A typical silumin is the eutectic alloy with 88% Al and 12% Si.
 Having good castability, corrosion resistance, high ductility
and low density.

23.  Titanium has two allotropic forms: upto 880OC, it exists
as a-titanium hexagonal close packed structures
(HCP)and at higher temperatures as β-titanium (BCC)
 It is a strong, ductile and light weight metal, density of
pure Ti is 60% of steel.
 High corrosion resistance and high strength at elevated
temperatures and widely used as a structural material.
 Suitable for cold and hot working and has good
weldability.
 Machinability is much inferior to steel

24.  The most important alloying elements for titanium are
Al, Cr, Mn, V, Fe, Mo and Sn which considerably increase
the mechanical strength.
 Higher creep resistance, higher fatigue strength, highest
specific strength and good corrosion resistance.
 Responds to heat treatment by precipitation hardening.
 Ti-6Al-4V is the most widely used alloy, accounting for
about 45% of total titanium production.

25.  Used for aerospace structures and turbines due to the
high specific strength, corrosion resistance and strength
at elevated temperature.
 Titanium is used in the construction of leaching and
purification plants for cobalt production.
 Due to the higher corrosion resistance, titanium is also
used in various chemical processing equipments, valves
and tanks.

26.  Used for aerospace structures and turbines due to the high
specific strength, corrosion resistance and strength at elevated
temperature.
 Titanium is used in the construction of leaching and purification
plants for cobalt production.
 Due to the higher corrosion resistance, titanium is also used in
various chemical processing equipments, valves and tanks.

27.  Magnesium has the HCP crystal structure.
 It is lighter and less ductile than aluminium.
 It is having poor modulus of elasticity, poor resistance
to wear, fatigue and creep.
 Its response to strengthening mechanisms also is
relatively poor.
 Solubility of aluminium in magnesium increases with
temperature
 This alloy responds well to age hardening also

28.  Addition of aluminium to magnesium increases
strength, hardness and castability.
 Addition of manganese to magnesium has very little
effect on the mechanical properties, but it improves the
corrosion resistance.
 Magnesium-aluminium-zinc alloys have higher
mechanical properties and good corrosion resistance.
 In general, magnesium alloys have poor ductility and
formability, but poor fatigue and stress corrosion
resistance.