NON FERROUS METAL (Other than iron as a major constituent) .
NON FERROUS MATERIALS Elements other than iron (OR) Other than iron is a major constituent More costly than ferrous materials CHARACTERISTICS: Lighter in weight Electrical and thermal conductivity Resistance to corrosion
A metal containing little or no iron content NON-FERROUS METAL Aluminum Bronze Brass Copper Lead Nickel Tin
COPPER ( செம்பு ) Its a oldest and most widely used non-ferrous metal in industry. Melting point 1083˚C
Copper extraction Copper is converted in to IRON SULPHIDE and COPPER SULPHIDE MATTE OXYGEN INTRODUCED ( Iron sulphide in to Iron oxide) (COPPER SULPHIDE IN TO AN IMPURE COPPER) Impure copper is purified to pure copper Ore ( Copper pyrites) Chemically combined (With Iron and Sulphur)
Properties of copper High electrical conductivity High thermal conductivity Excellent resistance to corrosion It’s a soft, ductile and malleable. It can be worked in hot and cold condition It cannot be welded Its become brittle just below its melting point.
Applications of copper Mostly used in cable telephone cables Cables for computer network Printed circuit boards connectors Used in the form of sheets and in agriculture purposes Domestic items like vessels Used chemical and food industries Used as a tubes in heat exchangers. Used mainly in the manufacturing of brass and bronze alloys
COPPER ALLOYS Copper alloyed with number of elements to provide a range of useful alloys Characteristics: high thermal and electrical conductivity high corrosion resistance high ductility and formability
Other elements results Small amount of beryllium or chromium to copper give high strength alloy A small addition of cadmium gives a significant increases in strength with little loss in electrical conductivity Addition of terrilium gives very good machinability
BRASS Its an alloy of copper(cu) and zinc ( zn ) sometimes other elements like tin( sn ), lead( pb ), aluminium (al) and manganese( mn ) may be added. Upto 36% of zinc, the brass is a single phase α solid solution ----- These alloys are called α brasses -These are soft, ductile and easily cold worked More than 36% of zinc have two phases α and β phases at room temperature -- these are stronger than α brasses
Brasses
Characteristics of brasses Its stronger than copper Low thermal and electrical conductivity than copper It can be into moulds, drawn into wires, rolled into sheets and turned into sheets. For improving machining property in brass they are adding 1 – 3% of lead . The brass color varies from reddish to white depend on the amount of zinc present
Types of Brasses Depend on the copper and zinc they are, Gliding metal Cartridge brass Standard brass Naval brass Admiralty brass High tensile brass Free cutting brass
Bronze Its an alloy of copper(cu) and tin ( sn ) They have high strength with corrosion resistance than brass The strength of the bronze increase with the increase of tin content. The tin content should be below 12% because they lead to be brittle Bronze can be shaped or rolled into wires , rods and sheets
Bronze வெண்கலம்
Types of Bronze Bell bronze --------- 78 cu, 22 Sn (tin) Phosphor bronze – 88 cu, 10 Sn 0.3 P, 1 Zn, 0.7 Pb Silicon bronze ------ 95 cu, 3 Si , 1 Mn , 1 Fe Aluminium bronze – 89 cu, 7Al, 3.5 Fe, 0.35 Sn Coinage bronze ---- 95.5cu, 3 Sn , 1.5 Zn Leaded bronze ----- 75 cu, 5 Sn , 18 Pb , 2 Ni
Leaded bronze Leaded bronze ----- 75 cu, 5 Sn , 18 Pb , 2 Ni
Gun Metal Gun metals are the alloys of copper(cu), tin( sn ) and zinc( zn ) Zinc act as a deoxidiser and it improves fluidity during casting Small amount of lead improve castability and machinability . Zinc is cheaper than Tin so we reduced alloy cost
Types of gun metal Admiralty Gun Metal Leaded Gun Metal
Cupronickel Its a alloy of copper and nickel. It’s a single phase uniform solid solution Thus all copper nickel alloys are relatively ductile and malleable. They have better corrosion resistance It can be hot worked or cold worked. It can be shaped by rolling, pressing, drawing and spinning
CUPRONICKEL
Types of cupronickels S.NO ALLOY NAME COMPOSITION PROPERTIES APPLICATIONS 1 Cupro nickel 70 Cu, 30 Ni Good corrosion resistance Can be cast into any forms Salt water piping's , condenser tubings 2 Monel Metal 29 cu , 68 Ni , 1.25 Fe , 1.25 Mn Good corrosion resistance, Good mechanical properties Propellers, pipe fittings, condenser tubes, steam turbine blades, tanks, food and chemical industry plants 3 ‘K’ monel 29 cu , 66 Ni , 2.75 Al, 0.4 Mn , 0.6 Ti A heat treated alloy Good mechanical properties Used in motor boat propeller shafts
ALUMINIUM It’s a most widely used and important Non-ferrous material Characteristics of aluminium : Light weight ( 1/3 rd of weight of steel) High thermal and electrical conductivity Excellent corrosion resistance Non – toxicity Soft and ductile Low specific gravity High strength to weight ratio High reflectivity.
EXTRACTION OF ALUMINIUM Bauxite ore Purification Dissolved in fused cryolite ( Aluminium and sodium) Electrolysis process Aluminium
Aluminium Vs Copper Less cost than copper Specific gravity of aluminium 2.7 compared to 8.9 for copper Better electrical conductivity (20 % more than copper) But it cannot be welded or soldered. To over come this defect they are using tin coating on aluminium Aluminium having low strength, for that its alloyed with Cu, Ni, Mn , Mg and Si
Aluminium alloys Aluminium can be alloyed with one or more elements like Cu, Ni, Mn , Mg and Si These elements convert the soft and weak elements into strong and hard non metal CHARACTERISTICS: Properties less than steel, Equal to alloys Superior to manganese alloys
Types of aluminium alloys Heat treatable aluminium alloys Non – Heat treatable aluminium alloys
Heat treatable aluminium alloys Using age or precipitation hardening we cannot strengthens the aluminum alloy. Al – Cu Alloys Al – Cu – Ni Alloys Al – Mg – Si Alloys Al – Li Alloys Al – Zn – Cu Alloys
Non – Heat treatable aluminium alloys These alloys are strengthened by cold working operations Important Non – Heat treatable aluminium alloys are Al – Mn Alloys Al – Mg Alloys Al – Si Alloys
Al –mg sheet
Al –Mg alloy .
Al-Si Alloy .
Al – Cu Alloys Duralumin Y-alloy
AGE or PRECIPITATION HARDENING It’s a process of increasing the strength of an alloy ( Al – Cu Alloy) Step – 1 ------ solution treatment Step – 2 ----- - Quenching process Step – 3 ------- Ageing Process
BEARING ALLOYS For making bearings
Characteristics of a bearing material It should have sufficient hardness and wear resistance. It should have a low co-efficient of friction. It should have a sufficient melting point. It should have high thermal conductivity. It should have good casting qualities. It should have good resistance to corrosion. It should be tough , shock resistant and sufficient ductility.
Bearing Materials Widely used bearing materials: White metals Copper base alloys Aluminium base alloys Plastic materials Ceramics. The selection based on loading, running speed and service conditions.
1) White bearing metal Its either tin based or lead based alloys. It contain 10% antimony ( Sb ). Tin( sn ) + Antimony ---- form a intermetallic compound SbSn This form a small hard cubic crystals, termed cuboids. cuboid is a hard, low friction substance.
i ) Tin based bearing alloys They are called babbit metals. Sb 10 % , Sn 82 %, cu 4 %, Pb 4 % They are high quality high duty bearing material than lead based alloys. They are used in medium and high duty applications like in automobile industries.
ii)Lead based alloys These are cheaper than tin based alloy. Sb 13 % , Sn 12 % , Cu 0.75 % , As 0.25% , Pb 74 % Used in low pressure low speed applications.
2) COPPER BASED BEARING ALLOYS Plain tin bronze -- Cu 85 %, Sn 15 % Phosphor bronzes – cu 88%, Sn 10 % P 0.3%, Zn 1%, Pb 0.7% Leaded bronzes - Cu 75% , Sn 5%, Pb 18%, Ni 2% Sintered bronzes – Cu powder 90%, Sn powder 10% Phosphor bronze gives improved load bearing capacity . Leaded bronzes are less strong than other bearing bronzes. but they will sustain higher loads at higher speeds than white metal.
Uses of copper base bearing alloys Used in aero engines, Automobile and diesel crank shaft bearings. Vacuum cleaners Washing machines, Extractor fan Audio equipments
3) Aluminium based bearing materials It contain alloys of tin , copper and nickel The expensive tin is replaced by aluminium base bearing alloys. Sn (tin) 5.5 – 7 % , Cu 0.7 – 1.3 % , Ni 0.7 – 1.3 % , remaining aluminium Used in automobile big end and main bearings.
4) Plastic bearing materials 1. Nylons ( polymides ) 2. poly tetra fluro ethylene (PTFE or Teflon) They have very low coefficients of friction USES These bearings used in small load applications Particularly oil lubrication is impossible or undesirable
5) Ceramic Bearing Materials These bearings are used in small precision instruments like jewel bearings in watch movements Alumina used as a bearings in large speed precision movements.
Super alloy It is a general term used to describe the nickel base and cobalt base alloys which have been developed for use at elevated temperatures . Super alloys produce a combination of high strength at elevated temperatures up to 1000°C and resistance to corrosion.
Applications Blades for turbine and jet engines Heat exchangers, chemical reaction vessel components and heat treating equipment.