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ENGINEERING MATERIALS NICKEL AND ITS ALLOYS TITANIUM AND ITS ALLOYS
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Nickel and Titanium alloys

Jan 12, 2015

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Page 1: Nickel and Titanium alloys

ENGINEERING MATERIALS

NICKEL AND ITS ALLOYS TITANIUM AND ITS ALLOYS

Page 2: Nickel and Titanium alloys

NICKEL

Page 3: Nickel and Titanium alloys

PHYSICAL PROPERTIES

SILVERY WHITE METAL HARD AND DUCTILE MAGNETIC UPTO 355 DEGREE CELSIUS FCC WITH LATTICE PARAMETER OF 0.352 NM

AND ATOMIC RADIUS OF 0.124 NM MELTING PT. = 1728K HEAT OF FUSION = 17.48 KJ/MOLE

Page 4: Nickel and Titanium alloys

MECHANICAL PROPERTIES

THERMAL CONDUCTIVITY = 90.9 W/M/K YOUNG'S MODULUS = 200 GPa SHEAR MODULUS = 76 GPa BULK MODULUS = 180 GPa POISSON'S RATIO = 0.31

Page 5: Nickel and Titanium alloys

OCCURENCE

LATERITE ORES : (Fe, Ni)O(OH) GARNIERITE ORES : (a hydrous nickel silicate): (Ni,

Mg)3Si2O5(OH)4

PENTLANDITE ORES : Ni, Fe)9S8

ABOUT 40% FROM RUSSIA AND 30% FROM CANADA

Page 6: Nickel and Titanium alloys

EXTRACTION AND PURIFICATION

Commercial extraction is from sulphide ores. Nickel is recovered through extractive metallurgy. Concentration is done by froth floatation Next stage is roasting and reduction of the sulphide ore

which yields 75% pure nickel Refining is done by “Monds Process” Nickel is reacted with carbon monoxide at around 50 °C to form volatile nickel carbonyl. Any impurities

remain solid while the nickel carbonyl gas passes into a large chamber at high temperatures in which tens of thousands of nickel spheres, called pellets, are constantly stirred. The nickel carbonyl decomposes, depositing pure nickel onto the nickel spheres. Alternatively, the nickel carbonyl may be decomposed in a smaller chamber at 230 °C to create fine nickel powder. The resultant carbon monoxide is re-circulated through the process. The highly pure nickel produced by this process is known as carbonyl nickel.

Page 7: Nickel and Titanium alloys

APPLICATIONS

Household : Magnets, Coins, Rechargeable cells, Electric guitar strings

Industrial : Alloys, Wires, electric gadgets.

Laboratory: Catalyst for hydrogenation

Biology : Present in enzymes

Page 8: Nickel and Titanium alloys

NICKEL ALLOYS

Page 9: Nickel and Titanium alloys

ALNICO

“ALNICO” = Al + Ni+ Co + Cu(traces) + Ti (traces) + Fe

It is ferromagnetic and used in permanent magnets

8–12% Al, 15–26% Ni, 5–24% Co6% Cu, up to 1% Ti and balance is Fe.

Page 10: Nickel and Titanium alloys

GERMAN SILVER

Cu + Ni + Zn 60% copper, 20%

nickel and 20% zinc. Applications : silver plated cutlery zippers & jewellery musical instruments pipe fittings

Page 11: Nickel and Titanium alloys

INCONEL Family of austenitic nickel -

chromium based superalloys

PROPERTIES:

Oxidation & corrosion resistent

High heat resistence

Difficult to machine

APPLICATIONS :

Gas turbine combustors and blades.

Shafts

Rocket skins.

Page 12: Nickel and Titanium alloys

MONEL METAL COMPOSITION : nickel (up to

67%) and copper, with some iron and other trace elements

PROPERTIES :

difficult to machine

highly corrosion resistent

highly sonorous

APPLICATIONS:

submerged pumpsets

musical instruments

oilfield industry

earth moving drills

lab apparatus

Page 13: Nickel and Titanium alloys

NICHROME 80% nickel and 20%

chromium PROPERTIES: high melting point

high electrical resistivity

good stability from deforming

APPLICATIONS: resistance heating coils

rocket igniters

jewellery casting supports

ceramic manufacturing industry

Page 14: Nickel and Titanium alloys

HASTELLOY

COMPOSITION : Nickel + molybdenum +

chromium

PROPERTIES : High wear resistence

high corrosion resistance

high stress service

TYPES : A,B,C,D & its variants

APPLICATIONS : Bearings, pressure vessel linings,

chemical reactor pipes....

Page 16: Nickel and Titanium alloys

TITANIUM

Page 17: Nickel and Titanium alloys

PHYSICAL PROPERTIES

Low density high strength and ductility lustrous corrosion resistant and high melting point low thermal & electrical conductivity Paramagnetic

Page 18: Nickel and Titanium alloys

MECHANICAL PROPERTIES

Young's modulus =116 Gpa Shear modulus 44 Gpa Bulk modulus 110 Gpa Poisson ratio 0.32 Thermal conductivity = 21.9 W/m/K

Page 19: Nickel and Titanium alloys

OCCURENCE Titanium is always bonded to other

elements in nature

It is present in most igneous rocks and in sediments derived from them

living things and natural bodies of water

Titanium is contained in meteorites

found in coal ash

Major ores : anatase,brookite,ilmenite,rutile,titanite,perovs-kite and a few iron ores.

Page 20: Nickel and Titanium alloys

EXTRACTION AND PRODUCTION

4 MAJOR STEPS : - reduction of titanium ore into "sponge"

melting of sponge, or sponge plus a master alloy to form an ingot

primary fabrication, where an ingot is converted into general mill products such as billet, bar, plate, sheet, strip, and tube

secondary fabrication of finished shapes from mill products

KROLL'S PROCESS ( COMMERCIAL PROCESS) : -

2 FeTiO3 + 7 Cl2 + 6 C → 2 TiCl4 + 2 FeCl3 + 6 CSSO (900 °C)

TiCl4 + 2 Mg → 2 MgCl2 + Ti (1100 °C)

Page 21: Nickel and Titanium alloys

APPLICATIONS ALLOYING

PAINTS,PAPER,TOOTHPASTE,PLASTICS

CORROSION RESISTANT TOOLS

SURGICAL INSTRUMENTS

AIRCRAFT PARTS AND GEARS

MARINE VEHICLE PARTS

PLUMBING EQUIPENTS

TiCl4 IS USED TO PRODUCE MANY CATALYSTS.

SPORTS GOODS

DEGIGNER JEWELLERY

ORTHOPAEDIC IMPLANTS

Page 22: Nickel and Titanium alloys

TITANIUM ALLOYS

The crystal structure of titanium at ambient temperature and pressure is close-packed hexagonal α phase . At about 890°C, the titanium undergoes an allotropic transformation to a body-centred cubic β phase which remains stable to the melting temperature.

Some alloying elements raise the alpha-to-beta transition temperature (i.e. alpha stabilizers) while others lower the transition temperature (i.e. beta stabilizers).

Aluminium, gallium, germanium, carbon, oxygen and nitrogen are alpha stabilizers.

Molybdenum, vanadium, tantalum, niobium, manganese, iron,chromium, cobalt, nickel ,copper and silicon are beta stabilizers.

Page 23: Nickel and Titanium alloys

CATEGORIESAlpha alloys which contain neutral alloying elements (such as tin) and/ or alpha stabilisers (such as aluminium or oxygen) only. These are not heat treatable.

Near-alpha alloys contain small amount of ductile beta-phase. Besides alpha-phase stabilisers, near-alpha alloys are alloyed with 1-2% of beta phase stabilizers such as molybdenum, silicon or vanadium.

Alpha & Beta Alloys, which are metastable and generally include some combination of both alpha and beta stabilisers, and which can be heat treated.

Beta Alloys, which are metastable and which contain sufficient beta stabilisers (such as molybdenum, silicon and vanadium to allow them to maintain the beta phase when quenched, and which can also be solution treated and aged to improve strength.

Page 24: Nickel and Titanium alloys

GENERAL PROPERTIES OF TITANIUM ALLOYS

It is stronger than steel, but 45% lighter

It is not easily corroded

resistance to high temperatures

low thermal conductivity

low electrical conductivity

heat has no or negligible effect on dimension but it hardens on heating

higher resistance towards metal fatigue

no harm to biological tissues

Page 25: Nickel and Titanium alloys

ALLOY GRADES

BY VARYING THE TYPE AND COMPOSITION OF METALS ADDED, 38 DIFFERENT ALLOYS ARE USED FOR COMMERCIAL PURPOSES.

MAJOR ALLOYED METALS ARE ALUMINIUM, VANADIUM, CHROMIUM AND MOLYDENUM.

THESE ARE VERY VERY COSTLY ALLOYS.

Page 26: Nickel and Titanium alloys

Aerospace Applications

turbines shafts sheet metal work

Page 27: Nickel and Titanium alloys

Industrial Applications

Increased life of articles.

Reliability of machine parts

Pipings

Page 28: Nickel and Titanium alloys

AUTOMOTIVE

Engine parts such as connecting rods, wrist pins, valves, valve retainers and springs, rocker arms and camshafts, to name a few, lend themselves to fabrication from titanium, because it is durable, strong, lightweight and resists heat and corrosion.

Page 29: Nickel and Titanium alloys

Computer Industry

Modern Hard disks Modern pendrives

Page 30: Nickel and Titanium alloys

Human Implants

Surgical instruments Implants to repair

facture of bones...